pasta with beer-caramelized onions

Directions

1. Set your largest pot filled with water to boil, and cook your pasta to al dente. Just before draining the pasta, reserve 1/4 C of the pasta water to use later. Drain and rinse the pasta, and set aside.
2. While the pasta water is boiling, start slicing your onions. Slice onions in half, and then into as thinly sliced half-moon shapes as possible.
3. In a stainless steel or cast iron pan, melt the butter or heat the olive oil until hot over medium heat.
4. Add all of the onions to the pan, and cook until soft and translucent and onions have released a lot of liquid. This step doesn't need to be precise.
5. Pour in all of the beer to the onions and stir. Leave this to cook, stirring occasionally, until all of the beer is cooked out. You'll be tempted to turn the heat up to get this to go faster, but the slow cooking is what the caramelization is all about!
6. Continue cooking the onions, keeping a close eye on them but not stirring too often, until they are so deeply brown they're almost burned. Pour in all of the reserved pasta water, and use it to scrape up all of the onion that stuck to the bottom. If you can't get it all up with the 1/4 C of pasta water, add tap water 1 tablespoon at a time, or use any leftover beer.
7. Toss the caramelized onions with the pasta, season with salt and pepper liberally. If the pasta looks dry, toss in a tablespoon or two of olive oil.
8. This keeps several days in the fridge, and as I mentioned in the top note is very customizable! Lots of different add-ins work here.