Balsamic Caramelized Onions | The Best Caramelized Onions Recipe (2024)

FAQs

What is the secret to caramelize onions? ›

As soon as the onions start sticking to the pan, let them stick a little and brown, but then stir them before they burn. 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.

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.

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 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.

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.

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.

Adding baking soda makes the onions more alkaline, increasing the speed of the Maillard reaction so they brown more quickly. But it also imparts a chemical-like bitterness to the end result.

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.

→ Follow this tip: Making caramelized onions is a hands-on task that requires your attention. For even cooking, and to prevent burning, it's essential to check and stir the onions every five to 10 minutes.

You definitely want the flavor of butter in your onions—but butter has the tendency to burn. For insurance, use a combination of butter and oil, which has a higher smoking point. But how much do you use? Depending on the consistency you want your onions, you can use more or less fat.

Do you caramelize onions on low or high heat? ›

For most of the cooking process, the heat should be low or medium-low to prevent the onions from burning before they have a chance to soften and caramelize.

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.

Why are my caramelized onions bitter? It's likely you are cooking them too fast/on too high a heat, which results in burned, not caramalized, onions. The trick to caramelizing onions is low heat and slow cooking. It can take a while, especially if you start with a big batch.

Like I mentioned above, we want to get rid of all the water in the onions to allow for browning to take place. But once the onions do start to brown, water can be your best friend! Adding water periodically into the pan while caramelizing your onions will prevent burning.

Brown sugar is simply cane sugar with molasses added to it. Therefore, you are adding even MORE sugar, and more brown color, to your onions. Thus the caramelization is so much better and faster! If you don't have brown sugar, feel free to use regular cane sugar or even panela when caramelising onions.

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.

You don't want to slice them too thin or they'll cook too fast which could cause them to burn. You'll also want to start out with fat. I choose oil and butter. Butter gives it a good flavor and helps with the caramelization and the oil helps the butter not to brown too fast.