Do we really need a "recipe" for grilled cheese? The students in my Knife Skills class think that we do. Knife Skills is the only class where I don't give out recipes since the focus of the class is not cooking, but chopping. But we still have to eat, so we improvise a meal out of whatever we chopped up. Most of the menu changes, but one item has become so popular that I make it for every Knife Skills class: the grilled cheese.
We always end up with a ridiculous amount of sliced onions, and what better thing to do with them than to caramelize and turn them into a musky, jammy concoction that turns every dish to gold. As Marie Wolf from BreadBasketcase mentioned: "Caramelized onions improve almost everything, except maybe ice cream." I got an idea for a grilled cheese with granny smith apples and caramelized onions from a class I took with Didi Emmons about 5 years ago. The walnuts got added when I was trying to use up whatever was left over in the vacation house pantry on the last day of a ski trip 3 years ago. It was such an incredible sandwich that I haven't changed it a bit in the last 3 years (and I am a hopeless improviser). What can I say -- you can't mess with perfection.
Caramelized Onion, Apple, Walnut Grilled Cheese
For Caramelized Onions:
3 Tbsp olive oil, plus more as needed
2 Lb yellow onions, sliced
Salt (2 tsp Diamond Crystal Kosher / 1.5 tsp Morton's Kosher / 1 tsp table)
2 tsp balsamic vinegar
For the Sandwiches:
Good bread, sliced 1/2 inch thick (in Boston, I prefer to use Iggy's "country sourdough")
Unsalted Butter, softened
Walnuts or Pecans, coarsely chopped (either toasted or un-toasted are fine)
Granny Smith Apple, sliced 1/6" thick
Good cheddar, sliced 1/8" thick (I prefer 1 year old Cabot or Grafton Village)
To make caramelized onions:
- Set a large, heavy (not non-stick) skillet oven medium heat. Add the oil, onions, and salt. Cook stirring occasionally until onions get somewhat brown, 12-18 minutes.
- Turn down the heat to medium-low and cook stirring occasionally until onions are medium brown, about 45 minutes, adding more oil if they stick too much.
- Add balsamic vinegar, and cook stirring occasionally until onions are dark nutty brown, about 15 minutes. Take off heat. You'll have way more onions than you'll need for grilled cheese, but that's not such a bad problem to have.
- Have 2 pieces of bread ready for each sandwich and butter each piece on one side (be generous with butter -- you only live once :)
- Turn on the broiler.
- Set an oven-proof skillet, that can hold all the sandwiches you are making in one layer, over medium heat.
- Place 1 piece of bread per sandwich in the skillet, buttered side down. Arrange caramelized onions on top of bread, sprinkle with nuts, top with 1 layer of apples and then cheese. The order actually matters. You want the cheese to be on top so that it melts quickly under the broiler and the nuts to be next to the onions so that they stick and don't fall out. Cook the sandwiches until the bottom of the bread is golden brown.
- Pop the skillet under the broiler for 1-2 minutes, just until the cheese melts. Check every 20 seconds since broilers vary widely.
- Return the skillet to the stove top on medium heat. Top with the second piece of bread, placing it buttered side up. Flip the sandwiches, and cook until the bread is golden brown on the bottom.
- Serve with a German Riesling. It's a food/wine match made in heaven.