How to Make Caramelized Onions - The Recipe Critic (2024)

FAQs

How to Make Caramelized Onions - The Recipe Critic? ›

Start Sautéing: Add the onions and sauté for 5 minutes or until they start to soften. Continue Cooking: Add the water, reduce the heat to medium-low, and cook for 50 to 60 minutes, stirring every few minutes. Cook until the onions are very soft, golden brown, and caramelized. Be patient, this takes time!

While you can start the cooking process at medium heat, low and slow is the name of the game when it comes to caramelizing onions. Once your onions begin to soften and take on a golden hue, you'll want to reduce the heat from medium to medium-low or even low for the remainder of the cooking process.

Cooking instructions

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.

Simply put, caramelized onions aren't quick. It takes at least 45 minutes (and often over an hour) over low heat for the natural sugars in the onions to caramelize. Still, the time is totally worth it. Packed with irresistible umami flavor, caramelized onions add complexity to all sorts of savory dishes.

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.

While you can make caramelized onions with only one of either butter or oil, the best result will be if you use a bit of both. If you have to choose between oil or butter, choose a high quality oil (extra virgin olive oil or avocado oil).

So using baking soda will speed up the process. But you have to be careful. If you add too much, it will impact the flavor. Different recipes recommend anywhere from ⅛ to ¼ teaspoon per pound of onions (aka about 3 large onions).

Tip: the vinegar serves to deglaze the pan, adds acidity, and brings this recipe together by boosting the tangy and savory flavors of the caramelized onions. If the onions stick to the pan, that's fine.

Yes, you should cover the onions when caramelizing them. Covering the onions helps to trap the steam and heat, which aids in the caramelization process by softening the onions and allowing them to release their natural sugars. This results in a sweet and flavorful caramelized onion.

You can caramelize any kind of onion, but yellow or Spanish onions tend to offer the most balanced-sweet-savory flavor profile and are the most versatile for different dishes. Sweet onions, such as Vidalia or Walla Walla work too, but keep in mind that their flavor will become even sweeter once caramelized.

Why do you add baking soda to caramelize onions? ›

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.

Using baking soda to caramelize onions

Stir it in at the end of cooking for about 1 minute. Adding it too early will break down the onion fibers, turning them into mush.

A large cast iron or steel pan is essential for creating the best caramelized onions. A heavy pan is ideal because it evenly distributes heat and will cook the onions evenly. Even cooking = the best caramelized onions. Nonstick pans don't work quite as well and prolong the process.

Depending on the consistency you want your onions, you can use more or less fat. Just cover the bottom of your pan for jammy, soft caramelized onions, or add a little more for more structured, slightly charred caramelized onions. The more fat in the pan, the more the onions will fry rather than soften.

If you need to caramelize onions quickly, adding sugar or a pinch of baking soda (to raise the pH level and help them brown quicker) can help to speed up the caramelization process but truly they aren't a dish that cooks up quickly. If using baking soda I'd suggest about 1/4 tsp per pound of raw onions.

Stirring the onions and scraping down the sides of the pan often to ensure no strand darkens faster than another is key. A heatproof rubber spatula is the tool for this job; it's stiff enough to scrape the bottom of the pan and flexible enough to clean the sides.