Almost nothing bugs me more than when recipes say that caramelizing onions takes 10 minutes. You can burn onions in that time frame, but proper carmelization takes at least 40 minutes. This article sums up my anger on the issue. Luckily, caramelized onions can be prepared in advance, so you don’t have to go through the process every time that you want to use them in a recipe. I found a 5-lb bag of vidalia onions on sale last week for a price that I couldn’t pass up, so I decided to use those. You can caramelize any onion that you would like to.
Start by slicing your onions in half, and then slicing them into 1/4 to 1/2 inch moons. There is no need to be super precise. Place them into a large, heavy pot that has a lid. Sprinkle them with a little bit of salt. I used about 1 tsp for the 5 lbs of onions. Turn the heat to medium-low and put the cover on. Let sit for 15 minutes, which allows the onions to sweat. Remove the cover, and give them a good stir. They should look like they have released some moisture, but not brown at all. Keep the lid off, and continue to stir them every 10 minutes or so. I usually set a timer so I don’t forget to check on them. There is no need to hover; let them sit and do their own thing. They will continue to get darker as the time goes on. Once they start to stick to the bottom of the pan, you’ll have to keep a better watch over them. If you are doing a small batch of them, this could happen in 20-30 minutes. My 5 lbs took a little over an hour. At this point, turn the heat up slightly, and stir them every 1-2 minutes. Continue to stir them until they get dark brown, and look like this:
As you can see, they have greatly reduced in volume. I think that I ended up with about 2 cups of caramelized onions at the end. You can use the onions immediately, or store them in the refrigerator for a couple of days. You can also freeze them, which is what I did. I divided them into 1/2 cup servings and put them into freezer bags. Make sure to remove as much air from the bags as you can before freezing them. You can freeze the onions for up to 3 months. To use them frozen, first let them thaw, and then reheat in a fry pan. While it does take some effort in the beginning, having frozen caramelized onions on hand is great shortcut later. Enjoy!