Caramelized Onions Common Mistakes—and How to Avoid Them (2024)

FAQs

Caramelized Onions Common Mistakes—and How to Avoid Them? ›

Our Test Kitchen likes to use butter when caramelizing onions, as it offers the richest flavor. If you avoid dairy or don't have butter, you can caramelize onions in other fat such as margarine or olive oil. Add the onion slices. It's okay if they overlap a bit here because they'll shrink as they cook down.

Our Test Kitchen likes to use butter when caramelizing onions, as it offers the richest flavor. If you avoid dairy or don't have butter, you can caramelize onions in other fat such as margarine or olive oil. Add the onion slices. It's okay if they overlap a bit here because they'll shrink as they cook down.

If the onions aren't deeply brown after 50 minutes and you'd like to speed things up, you can turn the heat higher to get more caramelization. Stir continuously to prevent burning.

If the onions stick to the bottom of the pan, deglaze with a tablespoon of red wine vinegar, balsamic vinegar, or wine. I usually stick with balsamic vinegar because the flavor complements the onions perfectly. Not only will deglazing pull up tasty sticky bits, it will add even more flavor to your caramelized onions.

If you cover the pan, you'll trap steam, which will speed up their softening, heat them more quickly, and help release their liquid more quickly. Lift the lid a few times during this stage to give them a stir and make sure nothing is browning yet.

Caramelize the onions: Heat about 1 tablespoon of canola oil in a large skillet or dutch oven over medium-low heat. Once hot, add the onions and stir to coat. Let cook, stirring every 5-10 minutes, until deeply caramelized, about 1 ½ - 2 hours.

Just make sure not to exceed the ratio of two tablespoons per two onions, as you don't want to end up frying the onions. You only need enough oil and butter to coat the bottom of the pan without fully submerging the onions.

In addition to water, we have another secret ingredient: baking soda. We often turn to it to speed browning, since it creates a high-pH environment, which allows caramelization to occur more readily. Baking soda is also handy for softening vegetables because altering the pH helps weaken their cell structure.

It's not necessary, but it will add some additional flavor.

You can use just oil, or a combination of butter and oil—the choice is yours! If you pack too many onions into your pan, they'll steam and produce water. Eventually, they will caramelize—but it will take much longer to get them there.

Do you constantly stir caramelized onions? ›

Fold onions with a spatula, scraping bottom of pan to ensure they don't stick or scorch. Cook, stirring every 5 to 6 minutes and reducing heat as necessary to maintain a gentle simmer, until liquid has evaporated, about 35 minutes.

Salting caramelized onions is like the icing on the cake. They must have salt but don't make the mistake of salting the onions too early. Instead, salt them at the very end of the recipe. Salt makes the onions release moisture which can slow down the caramelization.

The trick is to leave them alone enough to brown (if you stir them too often, they won't brown), but not so long so that they burn. After the first 20 to 30 minutes you may want to lower the stove temperature a little, and add a little more oil, if you find the onions are verging on burning.

So adding water and covering the skillet causes the raw onions to wilt faster and more evenly as the water turns to steam. Then, uncover the skillet and begin a process of pressing the softened onions into the bottom and sides of the skillet for maximum contact—and maximum browning.

Unlike mushrooms, which shouldn't be salted until after they've browned, you should always salt onions before you start cooking them. Onions won't begin to caramelize until all the water in them has evaporated, and using salt will speed up that process, Caicedo explains.

When you add baking soda during cooking it changes the pH which increases the Maillard reaction causing the onions to brown more quickly. The higher pH also causes the onions to soften more quickly, which we cover below when we discuss the texture.