Wednesday, January 12, 2011

Roast chicken legs, version 2

Cutting up a whole chicken is like going to the gym.  Everyone agrees it's a good thing to do, but not that many people do it on regular basis.  This is one of the many lessons I've learned in the Things with Wings class.

A few months before I taught my first Things with Wings class, I exhaled a deep sigh of relief.  I have finally roasted a perfect chicken.  Not a whole chicken of course.  That would be impossible.  A perfect bird has a breast cooked to 150F and legs cooked to 180F.  On a whole bird, that's impossible to achieve even if you butterfly it.  So I went the divide and conquer route and voila -- perfect chicken.  But my euphoria was short lived.

The Chicken
When doing my research for the class, I've tasted every chicken available for sale in the Metro Boston area and found the tastiest one -- Misty Knoll from Vermont.  If there was a chicken pageant, Misty Knoll would surely win the title of Miss Chicken.  It's juicier, more flavorful, and more tender than any other chicken sold in the Boston area.  Giannone chickens run a close second, leaving all the other contestants far behind.    What I didn't count on was that these two chickens were only sold at Savenor's.  Add to that a hefty price tag and they turned out to be a somewhat unpractical choice for most of my students.

Cutting it up yourself
To teach my students to cut up a chicken, I gave them a demo, then gave them all birds so that they could practice.  Unfortunately, squeamishness put a damper on this relatively easy task.  As I found out, most people were put off by cracking joints, bones, and even a trace of blood.

The goal
My ideal roasted chicken tastes like chicken -- not like herbs, spices, and other distracting ingredients.  It provides an explosion of "roasty" flavor that only the Maillard reaction can produce (in other words -- browning).   It boasts juicy meat, and browned skin that is thin and easy to bite.  I don't like it when the skin is stiff and pulls off in one piece when you take a bite.  Just to clarify -- brown skin is not the same as crisp skin.  It's not that I don't like crispness, but it's not a requirement for me.  Once the chicken rests and releases it's juice, the skin often starts to soften anyway.

Does this work on a "normal" chicken?
When I started teaching the class, I quickly learned that almost no one was willing to go the extra mile of buying a Misty Knoll Chicken or cutting it up, so I decided to find out how well my recipe would hold up to a generic brand Whole Foods chickens that were cut up by Whole Foods. The breast recipe translated amazingly well with almost no modifications.  Whole Foods sells bone-in, skin-on chicken breasts.  The two breasts are still attached together.  If you ask, the butcher will removed all the bones for you.  You might need to do a little clean up at home, but it's minimal.  These little roasts don't have the wings attached, but the recipe works perfectly well without them and the chicken comes out juicy with complex "roasty" flavor.

The legs turned out to be much more of a challenge -- they were either coming out dry inside or completely pale on the outside with no depth of flavor.  I had several things working against me here.  Whole Foods legs were a lot smaller than Misty Knoll ones, and once I gave up cutting up the chicken myself, I couldn't rely on the back bone to give me at least a little extra bulk.  Whole Foods legs were also less forgiving of over-cooking.  While Misty Knoll legs were still tender and relatively juicy at 200F, Whole Foods legs were completely dry.

After doing extensive research of how other people solve this problem, I've tried the following:

Dropping the heat
I used Kenji Alt's slow roasting method that works so well on meats.  I pre-roasted chicken legs at 250F on a rack and then seared them in a hot skillet.  This resulted in the juiciest meat, but I felt I was missing out on the roasted flavor.  The shape of chicken legs didn't lend well to browning in the skillet.  Even when I tried to use thighs only (without drum sticks), they would only brown in parts because of irregular contact with the skillet.  It was a good dish, but no one would mistake this for "rotisserie" chicken.

Brining vs. Salting
I tried brining the chicken to see if it would stay juicier than just salting 24 hours in advance.  I only used salt in the brine (no sugar) so that I could compare apples to apples.  Both methods work equally well.  Brining offered a novice cook an advantage of easy control over the amount and even distribution of salt.  The disadvantage was that the large container with brine and chicken was a bit cumbersome to store in the fridge.  

Air Drying
Since dry proteins brown a lot better than wet proteins, I thought I'd try to make my chicken as dry as possible.  I tried roasting chicken legs at 400F that were dried with paper towels and left uncovered to dry in the fridge for 6 hours.  For control I roasted legs that were just dried with paper towels but didn't spend any time uncovered in the fridge.  To my surprise, they came out the same.  Air chilling in the fridge might have helped the crispness by a hair, but it didn't do anything in the browning department.

There is a great disagreement among cooks on whether to baste the roasted chicken.  Jacques Pepin says baste.  Thomas Keller says don't baste.  In this case, I am with Jacques.  I tried roasting chicken legs at 400F basting half of them.  The ones I basted browned faster and had way better flavor.  Why would Keller tell you not to baste?  He claims it prevents crispness.  But I would gladly trade a little crispness for better browning.

No one agrees on the best temperature to roast a chicken.  After trying high heat, low heat, and everything in between, I realized that the culprit was not the intense heat, but the size and shape of the legs.  No matter what temperature I used, by the time the skin browned nicely and tasted "roasted," the meat was dry.  What I needed was to make the legs more bulky, so that they didn't cook as quickly.  And that's when it hit me -- why didn't I just tie them together.  That almost doubled the volume to surface ratio giving me much more time to brown the skin.  I don't know why I didn't think of this earlier.  That's exactly what I do with the breasts.  Sometimes the best solutions are the easiest ones. A wonderful side effect of doubling up the legs was that they took almost exactly the same time as the breasts and could be done in the same skillet with the same turning and basting schedule (roast for 35-40 minutes flipping and basting every 10 minutes).  

How is this different from butterflying the chicken
Butterflying the chicken (cutting out the backbone and flattening the chicken out) is a trick most cooks have up their sleeve to help with the problem of dry breasts or gummy and bloody legs.  It's definitely a step in the right direction, but it's not perfect.  I find the butterflied bird always a tad short on browning, which means less "roasty" flavor.  By tying 2 breasts together and 2 legs together I increase the volume per surface area allowing more time for browning.  It also produces very neat little roasts which can easily be roasted in a skillet and given head start with browning on the stove top.  The results are similar to the Italian "Chicken under a brick" with way less hassle.  Pairing legs with legs and breasts with breasts also gives me much more flexibility with doneness.  If the breasts are done 5 minutes before the legs or vice versa, I can easily remove them from the oven.  

A note on residual heat
One of the most difficult aspects of roasting is knowing when to stop.  If you've been cooking for a while, you know that the internal temperature will always continue to go up once you remove the food from the heat source.  The trick is knowing by how much.  When Kenji read my previous post on residual heat in the chicken breast roast, he thought my findings a little suspicious.  I reported that my 1.5 Lb roast went up about 20 degrees during 15 minutes of rest.  Kenji suspected that this temperature hike was due to me leaving the thermometer in the chicken while it was resting.  He suggested that the thermometer might be conducting heat from the outside layers to the inside and reporting a much bigger temperature rise than is really happening.  He said that in all his testing of roasted chickens at Cook's he only noticed a 1-2 degree rise.  Since Kenji is never wrong when it comes to data, I decided to do more testing.  I tested by breast roast by removing the thermometer after the initial test and reinserting it 15 minutes later.  Still 20 degree rise.  But when I tried testing how much the temperature went up in a butterflied chicken, I got almost the same results as Kenji -- the legs went up by only 1-2 degrees and the breasts by 7-10 degrees.  What's going on here?  

There are 3 factors responsible for such different results: the bulkiness of the roast, different roasting temperature, and different internal temperature at the time of removal from the heat source.  My chicken breast roasts might only weigh 1.5 Lbs, but their volume to surface area ratio is large (in other words, they are very bulky).  A butterflied chicken has about half the volume per surface area.  Another difference is the roasting temperature.  My chicken breast roast was cooked at 450F, while the butterflied chicken was cooked at 400F.  The higher the roasting temperature, the more the internal temperature goes up during rest.  The final factor is not something I've heard discussed before, but it seems to make a difference too.  It's the internal temperature at the time the roast is taken off the heat.  The higher the temperature, the less the roast goes up during rest.  For example, in a butterflied chicken, the legs barely go up because they are already at 180F, but the breasts go up more because they are only at 150F.  One way to think about it is that the whole system needs to come to equilibrium (in other words, all the meat and the air surrounding it will eventually come to the same temperature).  As soon as the roast is out of the oven, the temperature of its outside layers drops very quickly, so they'll continue to warm up 130F inside much more than 180F inside.  

A roasted piece of meat is a very complex thermodynamic system.  Until you do the testing, it's hard to predict how much residual heat you'll have.  I have now roasted more than 20 chicken legs at different temperatures taking careful notes and here are my findings.  My tied up roast made of two 9oz legs (they are the small Whole Foods legs), roasted at 450F to 175F*, goes up to 185F after resting 10 minutes and then start to cool off.  By contrast, the chicken thighs that were not tied up together that I slow roasted at 250F and seared in the skillet only went up 1 degree.  So, the moral of the story is that residual heat depends on many more factors than whether you are cooking chicken or beef and how much it weighs.    

Thanks Kenji for such a thought provoking observation!

Roasted Chicken Legs, Version 2

Salting (1-4 days in advance)

You'll need:
Chicken legs
Salt (Diamond Crystal Kosher if possible)

I prefer to salt my chicken at least a day before cooking to enhance its flavor. Dry your chicken thoroughly with paper towels (no, there is no need to rinse it before or after you cut it up). Season with salt on both sides and inside the skin (pull it off the thighs and tops of drumsticks, salt the meat, and cover back up with the skin). I use 2 tsp Diamond Crystal Kosher salt (or slightly over 1 tsp table) for 4 small legs (9oz each). Refrigerate for 24 hours or up to 3 days. I do it in a large zip lock bag.

Press chicken between paper towels to dry very thoroughly.

You'll need:
1 garlic clove (optional)
black pepper
kitchen twine

If using garlic, grate it on a microplane zester or mash to a smooth paste using your favorite technique.  Rub it all over chicken legs including under the skin on the thigh part of the legs.  Sprinkle chicken with pepper on all sides.  Put 2 legs together so that the flesh side of the thighs comes together and the skin side is on the outside.  Tie them together using kitchen twine.

Step 1
Step 2
Step 3

If you got two right or two left legs, it will look like this picture.
If you got a right and a left leg, it will look like this.


For 2 chicken legs, you'll need:
an appropriate skillet (see below)
2 tsp canola oil
2 tsp butter, melted
2 large carrots, cut into 1/4 inch thick planks
instant read thermometer

Preheat the oven to 450F with the rack in the middle.  Now you need to find a good skillet to roast this chicken in. Ideally, you need a heavy bottomed skillet with stainless steel interior (All-Clad or equivalent). This type of skillet will ensure crispy skin, prevent the chicken from sticking, and will produce a lovely sauce. Well-seasoned cast iron will perform the first two tasks beautifully, but will get damaged during sauce making process (deglazing and the acidic ingredients used in the sauce will ruin both the pan and the sauce). Enamel coated cast iron (like Le Creuset) will work well too. Non-stick might not be safe to use at such high temperature, and it will not give you a sauce since there'll be no lovely brown bits stuck to the bottom that you can deglaze.

Set your skillet on the stove-top over high heat. Add 2 tsp canola oil and wait for it to get very hot (oil will ripple and just barely start to smoke).  Place the tied legs in the skillet. Cook for 1 minute, then place the skillet in the oven. Roast for 10 minutes. While the chicken is roasting, slice 2 large carrots into wide thick planks. We'll place these carrots on the exposed parts of the skillet to prevent them from burning and ruining the fond (brown bits in English) and setting off fire alarms.  If they burn by the end, just discard them.

Have a burner ready on high heat if using electric (or just turn it on for gas). After 10 minutes, flip the chicken onto the other leg and place the carrots around it (as many as necessary to cover the exposed parts of the skillet in one layer). Cook for 1 minute on the stove top, baste with melted butter, then place the skillet in the oven. Roast for 10 minutes. Flip the chicken again.  Flip the carrots since they are probably starting to burn now. Baste with remaining butter and pan juices when you run out of butter.  Put in the oven for another 10 minutes.  Flip the chicken the last time. Baste with the pan juices.  Put in the oven for another 5 minutes.  Start testing for doneness.

Testing for Doneness
Insert a thermometer sideways between 2 thighs. If it reads 170F*, you are done. Test at least 3 spots to make sure you got the center. If all the readings are 170F or above, chicken is done. If not, continue to roast, checking the temperature every 3-5 minutes.

If you want both legs to retain crispy skin, set them vertically on a ring mold over a plate (or find some other system for keeping them vertical and letting the air circulate freely around the legs).  If you don't care that one of the legs will have a softer skin (I personally don't mind it), just place the chicken on a warm plate.  Let rest 20 minutes.  The temperature will go up to about 180F degrees during the first 10 minutes of rest, and will get down to pleasant eating temperature during the next 10 minutes.  You can make a pan sauce while you wait (see the chicken breast recipe for directions).  Remove the strings, separate the thighs and serve.

* When I originally wrote this post, I roasted legs to 175F.  With more testing, I found that 170F results in more tender and juicy chicken.


Anonymous said...

So what was the 3rd best tasting chicken?
Yep, Savenors is painfully expensive :-P

Helen said...

Third best? I am guessing the "Free Bird" brand from Russo's in watertown.

Anonymous said...

Your engineering background puts you in the same league as Alton Brown--a food scientist.

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Best regards,