(there should have been a picture here, but I ate it all)
1. Beer Selection – This is the most important step, no lie. Most onions will produce the same flavor, and if you follow Step 3, you’ll get the same general results. The beer adds a lot to the final flavor. Some will produce an almost red wine like sweetness, while hoppy beers add a little bitterness (but very little to no hop flavor). Experiment as you will. Darker beers leave more beer-specific flavors behind, while lighter beers tending to produce what I’d call a traditional beer caramelized flavor. Great way to use up the undrinkable stuff people bring to your parties too. Cider works, but you’ll get some apple notes, so be warned.
2. Onions – I prefer big white onions or sweet yellow. Rarely do red this way, but it works too. There’s no onion I’ve NOT turned into beer caramelized onions, but I tend to aim for whatever will produce the most final product. This article talks about red onions turning an ugly green-tinted brown. And recommends yellow.
3. Cut off the root and the tip of the onions. Then cut the onions in half. Slice it into strips or dice, whichever best fits your dish/use of the onions. Add 1 tablespoon of high heat-friendly oil to the pan and heat on a medium to low heat. Add the onions. Add a 2nd tablespoon of oil over the onions, then give everthing a good stir to coat. You can check on the onions about every 5 minutes. Lower the heat if there’s any burnt spots. When they’re good and light to medium brown, they’re ready for the final step.
4. De-glaze the pan with 4 oz of beer. Scrub the fond (the browned bits stuck to the pan) and fold into the onions. You’ll cut the heat when you’ve got nothing left of the liquid but a brown, sauce-like liquid in the bottom of the pan.
5. Let the onions cool, then salt them. Store for a week in the fridge or freeze em and keep for a couple of months.