Fun Fact Friday Caramelizing Onions Recipe

It’s an amazing alchemy when onions turn into caramelized heaven. Sure, I could throw some onion powder into a dish if I needed umami, but nothing replaces the sweet-sour-brown magic what-could-last-forever onions do when they’re cutting, sweating, and cooking down low and slow.

What’s more, for every 4 whole onions I slice, I consider the following: the oil-butter combo; the maillard reaction; and when to stop cooking, i.e., produce a certain shade of brown and a depth of flavor without burning. I can frequently amplify the natural flavor of the onions by adding just a pinch of salt.

That wasn’t the case when I was going for flavor but caramelized. For that, I needed a half teaspoon of sugar and some serious low heat.

The color of the onions changed from pale yellow to a deep brown. I didn’t know it at the time, but I was on my way to making some gourmet jam.

Onions have a sweet side, a flavor they express when cooked long enough that they turn dark and emit a gradient of deliciousness. Nutritionally, they’re calorie-light and flavor-heavy, so they’re a great fancy add-in to all sorts of meals.

Ingredients

Yellow Onions:
They are abundant in fiber and antioxidants and impart sweet flavors.

Olive Oil:
Fats that are good for you don’t just help your heart; they also add delicious rich flavors to a whole range of foods.

Unsalted Butter:
Contributes to creamy texture, contributes vitamin A.

Salt:
Elevates taste, equalizes sweetness and richness.

Sugar:
Optional, increases the inherent sweetness of onions.

Balsamic Vinegar:
Not required but good to have for adding a little zest, helping to scrape up any fond that may be stuck to the bottom of the pot, and keeping things relatively low in pH.

Ingredient Quantities

• 4 large yellow onions
• 2 tablespoons olive oil
• 1 tablespoon unsalted butter
• Pinch of salt
• 1/2 teaspoon sugar (optional, to enhance sweetness)
• 2 tablespoons balsamic vinegar (optional, for deglazing)

Instructions

1. Slice the 4 large yellow onions thinly and evenly, in the same direction, from the top of each onion to the bottom.

2. In a wide frying pan, warm 2 tablespoons of olive oil and 1 tablespoon of unsalted butter over a medium flame.

3. After the butter has melted, the sliced onions are added to the skillet, where they are stirred to coat them evenly in oil and butter.

4. Add a bit of salt to the onions, and if you like, throw in 1/2 teaspoon of sugar to bring out their natural sweetness.

5. Over medium heat, sauté the onions so they beg for your mercy. While you don’t want them to burn, you also don’t want them to achieve even, prism-like slices of gold. Perfection is not the endgame here. Cook them for about 30 to 45 minutes, and you’ll reach sweet heaven.

6. While the onions are cooking, reduce the heat a little if they start to brown too fast. The aim here is to get them to a deep, rich golden brown color.

7. Should the onions become adhesive, pour in 2 tablespoons of balsamic vinegar and use it to deglaze the pan, scraping any stubborn bits off the bottom to ensure even cooking.

8. Cook and stir the onions until they’re soft and deeply caramelized. Adjust the heat as necessary.

9. Sample the onions and correct the seasoning with additional salt, if required.

10. When you have finished, take the onions off the heat and let them cool a bit before serving them or using them in a dish you love.

Equipment Needed

1. Chopping surface
2. Cook’s knife
3. Skillet or frying pan, wide
4. Spatula or wooden spoon
Spoons for measuring

FAQ

• What type of onions are best for caramelizing?Caramelizing is best left to yellow onions. Their sugar concentration is high, and it is this that makes for a caramel in any case. What we get then in the end is the flavor, or in truth, the umami of flavor: sweet, rich, and oniony.
• Can I use only olive oil or butter?While the mixture of olive oil and butter gives flavor and acts as a safeguard against burning, you can use just one. Olive oil alone will give a lighter taste, while butter alone will give a richer taste.
• Why add sugar when caramelizing onions?Adding sugar is not necessary, but it does help speed up the caramelization of the onions and makes them taste sweeter, which is especially helpful if the onions you are using are not very sweet to begin with.
• How long does it take to properly caramelize onions?To attain a deep brown color in caramelized onions, the cooking time can range from 30 minutes to 1 hour. Heat and slice thickness are factors in determining this cooking timeframe, with heat intensity and slice thickness both suggesting a longer or shorter time when varied.
• What’s the purpose of adding balsamic vinegar?Using balsamic vinegar is not required, but it does aid in deglazing the pan and adds richness to the flavor while freeing any caramelized pieces stuck to the bottom.
• Can I store caramelized onions for later use?Indeed, they may be kept in an airtight container in the refrigerator for up to a week or frozen for longer storage.
• What are some dishes that use caramelized onions?On burgers, pizzas, and in sandwiches, caramelized onions are awesome. Mixed into dips, they’re fantastic. Even as just a topping on a steak or roast, they’re glorious.

Substitutions and Variations

Red onions or sweet Vidalia onions can replace yellow onions when another flavor is desired.
If desired, avocado oil or canola oil can take the place of olive oil.
Ghee or plant-based butter can be used in place of unsalted butter for a nondairy option.
A sprinkle of salt can be intensified by using sea salt or kosher salt, depending on what is at hand.
Honey or maple syrup can be used as natural sweeteners in place of sugar.
You can substitute balsamic vinegar with apple cider vinegar or red wine vinegar if you want to deglaze with different flavor notes.