How to make potato gnocchi

Wrong season.  I know.  If I was a cooking magazine, I would wait to publish this until fall.  But I am sure you'll forgive me, particularly if I give you a good recipe for potato (and sweet potato) gnocchi.

Why did I decide to make sweet potato gnocchi in April?  I needed a picture for a Gnocchi class that I have in the works and sweet potato gnocchi are probably the most photogenic of them all.

If you have been traumatized by a bad gnocchi making experiences, I just want to assure you that it's not you -- it's the recipe.  I don't know why there are so many recipes in existence that result in either slimy potato blobs disintegrating as you try to cook them or dense rubber balls?

Here is what you need to make feather light little pillows:

Scale
Without a scale, the odds of you getting the correct ratio of potatoes to flour are very slim.  My medium potato and your medium potato can be very different, and my cup of flour and your cup of flour can be very different too.  Can't you adjust based on how the dough feels?  No.  Adjusting means more kneading, which means more gluten development, which means more chew.  If you want rubber balls, go ahead and adjust.  If you want feather light pillows, get a scale.

Potato ricer or a food mill
Both of these tools will do the job of pureeing and fluffing up the potatoes, but they might not be found in every kitchen.  Don't use a food processor since it will compress the potatoes.  If you don't have either ricer or food mill, I would suggest getting a ricer -- it's easier to store and cheaper.

Use Boiling not Baking Potatoes
You need boiling potatoes (the ones that keep their shape after cooking).  If you use russets (baking potatoes), you'll end up with slimy disintegrating potato blobs.  Yukon gold produce the best possible gnocchi both in flavor and texture when I get them from the farmer's market in the fall.  Yukon gold potatoes from a regular store can be somewhat unpredictable and can result in gnocchi that don't hold their shape.  Red bliss potatoes produce the most reliable (if not absolutely heavenly) results and that's my choice of potato year round.

For the sweet potato version, I combine boiling potatoes (red bliss or yukon gold) with sweet potatoes in the ratio of 55% cooked and riced boiling potatoes to 45% cooked and riced sweet potatoes.  Buying sweet potatoes can be very confusing since many of them are sold as "yams."  For this recipe, I prefer Beauregard sweet potatoes (usually sold as "sweet potato") or Jewel yams.  Red Garnet will work in a pinch, but they are less sweet and more watery.

Potato gnocchi

Serves 6 as the first course

For the dough:
1.5 Lb (680g) red bliss or yukon gold potatoes
unbleached all-purpose flour (see the recipe for instructions on measurement)
Salt (see the recipe for instructions on measurement)

For shaping:
Semolina
Unbleached all-purpose flour

Dough

1. Fill a pot that can later hold a steamer insert with 3 inches of water. Set over high heat and bring the water to a boil. Put potatoes into the steamer insert, set over pot and cover. Reduce heat to medium and steam until potatoes are tender when pierced with a toothpick, 35-50 minutes.
2. Cool potatoes for 5 minutes, peel them while still hot.  Inspect potatoes and discard any parts that are black, gray or suspicious looking.  Put potatoes through a potato ricer or food mill and place in a large bowl.  Weigh them to see how much you got (make sure you tare the bowl before adding potatoes).  Cool potatoes to room temperature, 30-45 minutes (you can speed things up by placing them in the fridge and stirring every 10-15 minutes).
3. Divide the potato weight (the final weight after cooking and ricing) by 2.8.  That's your flour weight.  For example, if you had 600g of riced potatoes, you'd need 214g flour (600/2.8).
4. Divide the potato weight by 100 to get the salt weight.  For example, if you had 600g of riced potatoes, you'd need 6g of salt.  Salt is much easier to measure in grams than in fractions of ounces.
5.  Add the salt and the flour to potatoes. Toss with your hand to distribute flour evenly.  Gently knead the dough with your hand just until it comes together (don't over mix or the gnocchi will be tough). It should feel a little dry at first, but should come together into a rough and soft ball.  Flatten it into a thick disc.  Shape immediately.

Shaping

1. Line a large cookie sheet with parchment paper or foil, and sprinkle generously with semolina.
2. Dust the dough with all-purpose flour on both sides and place on a work surface.
3. Cut the dough into 2/3 inch thick slices (like slices of bread).  Cut each slice in half lengthwise to give you strips.  Roll each strip with the floured palms of your hands on a floured work surface into a 2/3 inch ropes (use all-purpose flour for this). Cut the ropes crosswise into 2/3 inch pillows using a pastry scraper (you can also use a knife on a cutting board).  Sprinkle the pillows with all-purpose flour and gently toss.  Place them on the cookie sheet. Don't let the gnocchi touch each other or they'll stick together. After shaping, you can keep the gnocchi at room temperature for several hours.  Don't cover the gnocchi, or they'll get soggy.  

Cooking

1. Bring a large pot of very generously salted water to a boil.
2. Warm up a large serving bowl in the oven at 200F.
3. Bring the cookie sheet with gnocchi close to the pot, lift the parchment paper and dump the gnocchi into the water. It's ok for semolina to get into the water. It will settle on the bottom of the pot and won't be present in the final dish. If the gnocchi got stuck to the parchment paper, dunk the whole parchment paper into the pot and gently shake them off into the water with a wooden spoon.  
4. As soon as the gnocchi are in the water, reach in under them with a slotted spoon to release them from the bottom of the pot.  
5. In 1-2 minutes, gnocchi should float.  Wait 30 seconds, and taste one.  If the center is too floury, cook another minute and taste again.  Spoon them out with a slotted spoon into the warm bowl. Dress with the sauce of your choice and serve immediately.

Sweet potato variation

Start with roughly equal weights of raw boiling and sweet potatoes.  For 6 first course portions, you'll need roughly 3/4 Lb boiling and 3/4 Lb sweet.  Steam them both until tender.  Weigh the boiling potatoes after cooking, peeling and ricing.  Divide that number by 1.2 and only use this amount of riced sweet potatoes (use the rest for another application).  When ricing sweet potatoes, make sure all the fibers stay in the ricer and don't end up in the final dish.

For example, if you have 330g riced boiling potatoes, you'll need 275g sweet potatoes.  That's 605g total.  Let's round it to 600g to make math a little easier.  Divide that by 2.8 to get your flour weight (214g) and divide by 100 to get your salt weight (6g).

You can add a few gratings of nutmeg and a few pinches of cinnamon to the sweet potato dough.

Why should eggs cost less than coffee?

The best eggs in Boston are not something money can buy.  They come from people who raise their own chickens.  By some stroke of luck, I've had a few chances to try the fruits of their labor, but due to department of health regulations I can't buy them legally.  

It all started when I lived in Belmont.  Who knew that 5 miles from the Prudential Center there were fresh eggs being laid with orange yolks that taste like liquid gold.  I've met these chicken ladies through my blog and my classes and they have generously shared their glorious eggs with me.  When we moved to Natick, I met another such kind soul who gifted me with a dozen of eggs from her back yard a few weeks ago.  I would gladly pay as much as necessary to buy them.  Unfortunately, it's not legal for these recreational chicken farmers to sell them to me and I can only accept so many freebies.  

A few weeks ago, I noticed two very expensive egg brands at Whole Foods.  Pete & Gerry's and Azuluna.  The light blue color of their shells caught my eye and I decided to try them in spite of their high price tag.  Both companies raise Ameraucana hens that are known for the blue-green tint of their egg shells and are supposed to be superior in flavor.  Azuluna are a bit more expensive because they claim to be "free range" rather than just "cage free."  It's hard to get straight dope on those terms, but from what I've read "free range" birds are the ones that actually get to roam outdoor while "cage free" birds don't.  So how do they taste?  Both are great!  Not quite my back yard chicken friends' level of great, but still noticeably better than all the other supermarket eggs (including organic and local ones).  

I have tried Pete & Gerry's side by side with Chip-in Farm and the difference was striking.

Pete & Gerry's on the left / Chip-in Farm on the right
Both are from Grade A Large Eggs

I'll have to try Pete & Gerry's side by side with Azuluna next time.  

Here are the rough prices (from memory, so don't quote me on this).  

Azuluna at Whole Foods -- about $3.50 for half dozen

Pete & Gerry's at Whole Foods -- about $3 for half dozen

Pete & Gerry's at Russo's -- about $2.50 for half dozen

When you really think about it, that's what you pay for coffee with foamy milk.  Aren't 6 truly wonderful eggs worth one cup of joe?

Poulet en Cocotte and Moroccan Braised Chicken, Version 2

It's hard to remember now why exactly I decided to try Cook's Illustrated recipe for Poulet en Cocotte.  French name aside, it's sweated chicked, that's what it is, and the idea didn't do much for me.  But I tired it anyway and learned that this unappetizing concept has enormous potential.

What is so good about Cook's recipe:

• Browning the chicken before covering and sweating.  No, the browning won't give you crispy skin in this case, but it will give you much more flavor.
• No additional liquid and limited amount of thoroughly browned vegetables.  This results in a very concentrated, wonderfully delicious sauce that naturally forms in the pot during cooking.
• Very low oven temperature helps keep the chicken tender and juicy.

My own improvements:

• Salt the chicken at least 24 hours in advance -- it's Judy Rodger's technique and she is never wrong
• Rub the chicken with mashed garlic (whole cloves grated on a microplane zester) all over and under the skin.
• Stuff the chicken (my favorite stuffing is prunes -- due to a happy childhood memory).  Not only is the stuffing yummy, but it helps the breast meat cook slower.  
• When the chicken is done, carve into serving pieces, dry off on paper towels and sear skin side down in butter (use a well seasoned cast iron or non-stick pan for this).  

While the legs were really lovely, I still found the breasts overcooked to my liking.  So I removed them for another preparation, discarded the breast bone and ribs, and used the rest of the chicken in parts (legs, back, and wings) for poulet and cocotte.  I browned the chicken parts and removed to a plate, then browned the veggies, returned chicken to the pot and proceeded just like the Cook's recipe.  Another option is to use 4 legs instead of 1 whole chicken.  Since the concept is similar to braising, I decided to try it with the Moroccan Chicken Braise ingredients.  There was less work than a traditional braise and results were even better.  

Here is what makes this technique better than my previous chicken braise recipe

• The skin is thinner and has better texture
• No need to make a stock (the chicken releases just the right amount of liquid during cooking)
• Cooking time is a lot shorter

Moroccan Inspired Chicken Braise, Version 2

If you don't have a Dutch oven, you can get good results in an oven-proof skillet with a tight fitting lid.  You can also buy a very inexpensive Dutch oven from Walmart made by Tramontina.  That's the one I use.  

Serves 4

4 chicken legs (about 10 oz each)

1 garlic clove, grated on a microplane zester
1/2 tsp black pepper
1 tsp ground cumin
1 tsp ground coriander
1/2 tsp cinnamon
1/2 tsp cardamom
1 Tbsp olive oil
1 medium yellow onions, sliced pole to pole

6 garlic cloves, peeled and trimmed
1 inch ginger, peeled and finely minced
1/2 preserved lemon (a.k.a Moroccan lemon), pulp removed, skin rinsed, and sliced paper thin
1 cup dried fruit (prunes, apricots, raisins, cherries, cranberries)

1 Tbsp butter

Salt

Salting the chicken (if possible, do this 1-3 days in advance)
Press the chicken pieces between paper towels to dry and sprinkle with salt on all sides including under the skin.

Browning the chicken and vegetables

1. Preheat oven to 250F.
2. Press the chicken pieces between paper towels to dry.  Rub with microplane grated garlic on the flesh side and under the skin.  Mix pepper, cumin, coriander, cinnamon, and cardamom and sprinkle all over chicken (you might have some spice mixture left over).
3. Set a 6-8 quart Dutch oven over medium high heat and add the oil. When the oil is hot, add chicken pieces skin-side down without overlapping (if your pot is not large enough, do this in batches). Do not disturb the chicken for at least 5 minutes. Regulate heat so that the chicken is making sizzling noises, but is not burning. When the first side is brown, flip the chicken to brown briefly on the other side, about 1 minute. Remove the chicken to a plate and set aside.
4. Add the onions and whole garlic cloves to the pot. Cook stirring occasionally until brown, 8-10 minutes. 
5. Add ginger, preserved lemon, and dried fruit.  
6. Return chicken to the pot.  Cover with foil and then a tight fitting lid and place in the oven until the thighs register 175F, about 30 minutes.
7. Remove chicken pieces and dry on paper towels.
8. Tilt the pan, and skim off excess fat. 
9. Set a large well-seasoned cast iron skillet (or non-stick) oven high heat.  Add 1 Tbsp butter.  When the butter foam subsides add the chicken skin side down and brown until crisp, about 2 minutes.  Serve with sauce over rice or couscous.

Spinach with Kumquats

Have you ever had a special occasion emergency -- I mean when you need to serve a special meal with no planning or shopping?  Just such a thing happened to me on friday.  Google's purchase of ITA Software, where Jason works, finally became official.  Everyone at ITA was waiting for the Department of Justice approval of this deal for 9 month!  Yes, as long as a full term pregnancy.  So it was a cause for great celebration for us.

Mergers and acquisitions are not special occasions normally covered by cookbooks and magazines, so I was on my own trying to figure out how pull a Bay Area meal out of my New England refrigerator.  We were having miso marinated sable for the third time that week, but there is no such thing as too much sable, trust me.  The side dish needed some help though.  It was going to be spinach with pine nuts and raisins.  Not that it wasn't a good dish, but we had it 3 times in a row that week.  That's what happens when you buy a bag of spinach at Costco, which I highly recommend by the way since you don't need to wash or stem it.  I was digging through my vegetables drawer for ideas and came across kumquats.  They are very aromatic little oranges the size of an olive that you can eat skin and all.  These ones were particularly tart and juicy and made a perfect addition to the spinach.  The dish turned out so well, I'll try to buy spinach and kumquats together on purpose next time.

Normally, we'd have a Riesling with this dish, but this was an occasion that required something bubbly.  Since neither one of us particularly likes Champagne (I know -- we are weird), Jason got us a Sparkling Rose from Bugey.  It was so good we finished the bottle in no time.

Spinach with Kumquats

Note: if kumquats are not an option, substitute them with a generous squirt of fresh lemon juice

Serves 4

1 Lb spinach
2 Tbsp olive oil
2 garlic cloves, minced
1/4 tsp red chili flakes or to taste (optional)
8-12 kumquats, sliced crosswise 1/4 inch thick
1/4 cup golden raisins, plumped in hot water for 5 minutes
2 Tbsp pine nuts
1 Tbsp butter
Salt and pepper to taste

1. If using mature spinach, remove the stems.  
2. Set a 12 inch skillet over medium heat.  Add oil.  When oil is hot, add garlic and chili flakes and cook stirring constantly until just a hint of color develops, 30-60 seconds.  
3. Add spinach, cover the skillet, and cook stirring occasionally until spinach is mostly wilted, about 5 minutes.  
4. Add kumquats, drained raisins and pine nuts.  Cook stirring to warm them through, 1-2 minutes.  Take off heat, stir in butter, and season with salt and pepper to taste.

Miso marinated sable

It's sable season again!  You might see it sold as "black cod" or "butterfish."  This dish was inspired by Ming Tsai's miso-sake marinated Chilean sea bass.  I believe he actually uses sable for it in his restaurant now.  There is only one problem with this fish -- after you taste it, nothing else that swims will ever measure up to it.

Miso marinated Sable

Fish substitutions: salmon, chilean sea bass, halibut, steelhead trout, or pretty much any relatively thick fillets that are not too dense.

Serves 4

4 sable fillets without skin (6oz each)
1 Tbsp sugar
2 Tbsp mirin (Japanese sweet rice wine)
1/4 cup canola oil
1/2 cup white miso (a.k.a. shiro miso)

At least 2 hours before cooking or up to 24

1. In a medium bowl, combine sugar, mirin, canola, and miso. Whisk thoroughly to combine. Add sable and coat with marinade. Cover and refrigerate for 2 - 24 hours.
2. Preheat the oven to 300F. Wrap a broiler pan with foil. Wipe all the marinade off the fish using paper towels and place it on the boiler pan. 
3. Turn on the broiler. Broil sable 4 inches away from the flame just until browned, 3-5 minutes. You might need to adjust the distance from the flame and timing to suit your broiler. Keep a close eye on the fish. If you see no color after 2 minutes, move it a little closer to the heating element. If you see too much color, move it further down. If the first side browned, but you still have more than half your estimated cooking time* left, flip the fish and brown the second side. 
4. To test for doneness, separate the flakes in the thickest part and look inside. Sable is done when a trace of translucency remains in the center or when an instant read thermometer inserted in the center reads 115F (thermometer only works well on pieces thicker than 1 inch).  If the fish is not cooked through after the broiling step, reduce the heat to 300F and finish cooking fish in the middle of the oven.

*Estimated cooking time and flipping: Plan on 6-8 minutes total cooking time (broiling, plus finishing in the oven if necessary) per inch of thickness. If you are working with fillets thicker than 1.5 inches or have a particularly powerful broiler, you'll be able to flip the fish and brown it on both sides. But if the first side takes more than half your estimated cooking time to brown, don't flip the fish. Just turn off the broiler and finish it in the oven.

The tricky business of buying farro

My heart sank as I peeled the $8.99 price sticker off the package of farro I got at Whole Foods.  It looked just like the package I bought a few years ago.  What made me suspicious was that after 20 minutes of cooking this farro was still no where near chewable.  Ah-ah! Under the price sticker was hiding that terrible word "Whole."  Could they choose a better place to put that sticker?  What's people's obsession with everything whole anyway?  We do peel eggs and bananas, don't we?  And we normally remove bones from fish even though they are full of calcium.  Why not sell farro in edible form?  If this was my first attempt at cooking it, I would vouch to never go near this grain again, but luckily I've cooked farro many times before and had a feeling I knew what trap I have fallen into.

Let me back up for a minute and explain what farro is.  It's the grains of an ancient wheat variety known as emmer.  I don't know if you noticed, but in the recent years farro has become the darling grain of restaurant chefs.  It has an earthy flavor without the feel of cardboard.  It gets tender quickly, but doesn't turn mushy easily.  It can be used in soups, in salads, in side dishes, and in risotto preparations instead of rice.  Cooking it is idiot proof (assuming you bought the correct product).  If you can boil boxed pasta, you can cook farro.

Buying farro is where things get hairy. The problem is that restaurants and recipe writers just call it "farro."  What they really want to say is "farro perlato" or "pearled farro."  "Pearled" grains are polished to remove most of the outer bran making them more tender.  When I first started cooking farro, about 5 years ago, I was lucky to only come across the pearled variety at my local Whole Foods.  I didn't know what the word "perlato" meant back then and didn't pay attention to it on the package.  I just bought it, cooked it, ate it, and was happy.

Since Whole Foods farro was a bit pricey ($9/Lb), I thought I found a bargain when I saw it at Christina's spices in Cambridge.  It was 4 years ago, so I don't remember the price.  They labeled it "spelt / farro."  Many on-line sources convince me that spelt and farro were the same thing, so I decided to try it.  I remember swearing when after 3 hours of cooking that stupid grain refused to become tender enough to eat.  That's when I thought I had farro buying all figured out.  I now had empirical evidence that spelt and farro were not the same thing and if I wanted farro, I needed to buy farro (ideally, imported from Italy since that's the type I had wonderful results with).

Little did I know that there was plenty more "wrong" farro I could buy.  As I found out on my recent trip to Whole Foods, not everything labeled "farro" and imported from Italy tastes like that heavenly grain I got in restaurants.  My local Whole Foods carries two types of farro.  One is labeled "whole farro" and the other is labeled just plain "farro."  Both of them look and taste just like spelt and in my opinion have no good culinary applications except for being added to salads in small quantities.  Now that I have tried whole farro, I wouldn't be surprised if the emmer wheat that farro comes from and spelt (another type of wheat) are indeed very similar.  The main difference is in how they are processed.  There is no reason why they couldn't polish spelt to rub off the bran like they do for farro perlato.  I have just never seen it sold that way.

Whole Farro on the left / Farro Perlato on the right

I asked the Whole Foods grains guy about farro perlato, and he said they don't carry it (at least not in that store).  I guess they are thinking that "whole" grains sell better to the health conscious Whole Foods shoppers.  The funny thing is that the nutritional labels for whole farro and farro perlato don't look any different.  They both have about the same amount of fiber and protein, so there are no great advantages to inflecting pain and suffering on your jaws.

"Now I am in trouble," I thought.  "Where will I get farro for my beans and grains class?"  I started googling for "farro boston" when a much easier solution dawned on me.  I buy all my cooking tools on-line.  Why not farro?  I was concerned that the shipping costs were going to be nasty.  But eventually, I found one company who sold it through Amazon at a very reasonable price of $12/Lb including shipping.


That's barely more than what Formaggio's in Cambridge charges for farro and definitely more convenient.  It breaks down to $6.50 for farro and $5.50 for shipping.  I ordered one pack to try.  It was perfect.  Now that I took a closer look, the shipping costs per package go down if you order more than one.  So buying 2 packs of this farro on-line is no more expensive than buying it at Whole Foods.

April 13, 2011 update:  Thanks to my wonderful reader, Chris, I was able to locate very inexpensive farro perlato in the Boston area.  I just called Formaggio's Kitchen in Cambridge and they indeed have farro perlato.  2.2 Lb bag sells for $9.  That's half the price of Whole Foods.  Whoever thought to seek a bargain at Formaggio's!

Once you are the proud owner of farro perlato, the rest is easy.  Bring lots of salted water to a boil like you would for pasta.  Stir in farro and cook until tender but toothsome, about 20 minutes.  Drain and serve hot, or rinse in cold water and serve in a salad.  You can also cook it using a risotto method just like you would Arborio (or any other type of risotto rice).

For the dish in the picture, I combined cooked, rinsed, and cooled farro with fennel and radishes (both were sliced on a mandoline), thinly sliced scallions, dill, and sectioned oranges.  I dressed this salad with lemon juice, olive oil, salt, and pepper.  The sexy looking fish on top is broiled sable.

How was it caught?

I sneaked out of many classes in my life, but "Fish sustainability" was the first class I ever sneaked into.  A strange wave of virtue and studiousness washed over me as I sat in the Whole Foods cafe.  I turned off my Kindle, got out my pen, and moved closer to the table where an inspiring talk on the catching methods was given to all the staff of the Framingham, MA store that might stand between you, the consumer, and that piece of tuna or mahi-mahi.  The "in-store educator" (that's what his business card said) even gave me a useful handout and was nice enough to answer all my questions after the talk.

As I found out from this class, you can now ask your Whole Foods fishmonger how the fish was caught.  He should know the answer or be willing to ask someone who does.  In theory, this should help you make an informed decision if you are trying to use the Monterey Bay Aquarium guide for choosing environmentally friendly fish.

Here are the fishing methods the class covered:

Long line --  uses a long line, called the main line, with baited hooks attached at intervals by means of branch lines called "snoods."  You can catch many fish at once without effecting the ocean floor.

Gill nets (aka "fixed nets") -- walls of netting which may be set at any depth.

Hook and line -- this traditional method uses one hook and one line.  least environmental impact, but very expensive.  Only 1% of commercial fish is caught this way in the US.

Bottom Trawls (aka "draggers") -- slow moving boats with large nets that drag along the sea floor.  The cheapest way to catch bottom dwellers, but is most harmful to the ocean floor.

Harpooning -- highly-selective method that targets larger species (sword and tuna).  No by-catch, no impact on the ocean floor, but expensive.

Purse seines -- netting encircles schooling fish that are targeted by sonar.  About 25% of US fish is caught this way.

High Seas Drift Nets -- nets are allowed to drift with the currents, and fishermen return later to retrieve what is caught.  This technique results in very large amount of by-catch and it was outlawed in EU since 2002.

I came home full of enthusiasm to see how this information helps me.  When I looked at the Monterey Bay Aquarium Northeast guide in the past, I got hopelessly confused because some species appeared in all three columns.  For example, here is what the guide says about the bigeye tuna:

Best choice: Tuna, Bigeye (U.S. Atlantic Troll, Pole-and-line)
Good alternative: Tuna, Bigeye (Troll, Pole-and-line)
Avoid: Tuna, Bigeye (Worldwide, Except U.S. Atlantic Longline)

Unfortunately, neither Troll nor Pole-and-line methods were covered in the Whole Foods class.  Is troll  the same as trawl?  No. Trolling is a method where one or more fishing lines, baited with lures or bait fish, are drawn through the water.  I couldn't get as much info on Pole-and-line, but from what I've read, it's roughly the same thing as trolling, and hook and line.  So, if Whole Foods tells you that their tuna is harpoon caught, good luck figuring what Monterey Bay Aquarium thinks about that.

No, you are not the only person getting a headache when trying to make a responsible choice at the fish counter.  It is indeed very complicated.  But I am very encouraged by Whole Foods' new red/yellow/green labeling system.  Unfortunately, there is no effective way for you and the staff member helping you at the fish counter to make an informed decision about which fish makes a more sustainable choice.  You simply don't have enough information.  But there are people at Whole Foods who do have that information.  They can do the research necessary to find out how healthy is the population of this particular species, what fishing method was used to catch it, how this method effects the habitat of this and other species, and how much by-catch results from it.  They can put all these factors on the scale and give the fish its sustainability grade.