Sorry—no shortcuts here! Just good old fashioned patience.
, in which proteins and sugars transform into an insane number of new flavor and aroma molecules. Together, caramelization and the Maillard reaction turn pungent raw onions into something so mild and sweet, it might well be dessert.
, for example, encourages a lighter degree of caramelization—an approach that's backed up by the recipes of many famous French chefs.The two samples on the left were free of baking soda, while the two sludge piles on the right were cooked with baking soda. Baking soda makes the onions more alkaline, which speeds up the browning reactions necessary for properly caramelized onions.
Adding sugar to the pot merely adds more sucrose to the formula, and will yield more simple sugars as a result. It's a lot like tossing more logs on a fire; what you'll end up with is not necessarily a better fire, just a bigger one. Try to enhance the process with extra sugar, and all you'll end up with are extra-sweet caramelized onions—I think way too sweet. You don't need more sugar, you just need enough heat and time to let the sugar that's already there do its thing.
But there are some significant negatives to using one for caramelized onions. First, a pressure cooker is a black box—once you seal the lid, there's no way to know what's happening inside the pot. You have no way to look inside the pot to see how browned the onions are, nor whether anything in there is burning .
Shallot: really good balance of sweetness, with both bright flavors and deep, rich ones, and just a hint of bitterness.In my experience, cast iron and stainless steel pans produce the best caramelized onions. Nonstick pans and enameled cast iron work less well, slowing down the caramelization process unnecessarily.
You don't have to cover the pan if you don't want to, it merely shaves some minutes off the total cooking time.As soon as the onions have softened, remove the lid so that the steam can escape; you won't have good browning in the presence of a lot of water, so it has to have a way to escape the pot.Continue stirring and scraping the onions every minute or two, keeping an eye for signs of browning on the bottom of the pot.