How to Make Caramelized Onions

Knowing how to make caramelized onions is one of the best kitchen skills for a home chef to learn! Onions, salted butter and water is all you need to have the most rich, sweet and savory ingredient to bring complex flavor to everything from pizza and pasta to burgers and fajitas.

Caramelized onions are beyond delicious and can amp up the flavor of so many dishes! They help make the best appetizer in this caramelized onion and bacon dip! They’re also incredible in onion gravy, this French onion tart and, of course, French onion soup!

Caramelized onions being stirred with a wooden spoon in a metal pan.

Caramelizing Onions

When you learn how to caramelize onions, you’ve learned how to make magic in the kitchen! Thinly sliced onions are sautéed in a pan over a long period of time, which releases the natural sugars in the onions. The end result is a unique, intensely, deep, rich, perfectly sweet flavor that will elevate any dish! They’re so good, we even love to eat them right out of the pan!

In addition to being totally delicious, onions are super healthy and contain many vitamins, minerals, calcium, iron, potassium, and antioxidants. You only need a good pan, onions, butter, water and some time to whip these up. Follow our step-by-step instructions, and you’ll have some amazing caramelized onions in just about an hour. I promise, these are well worth the wait! 

Ingredients Needed

Just 3 ingredients is all you need to have the most delicious complement to your entrees! After one bite of these onions, you’ll be wanting to add them to almost everything! You can find exact measurements in the recipe card at the bottom of the post.

  • Onions: I have found that caramelizing yellow sweet onions offer the best sweet and savory flavor.
  • Salted Butter: Some recipes call for sautéing the onions in oil rather than butter, and while that will work, butter provides extra richness that takes these to the next level.
  • Water: Deglaze with water as often as necessary to keep the onions from burning or sticking to the pan.

How to Caramelize Onions

Caramelizing onions to rich golden-brown perfection is a lot easier than you’d think. They definitely require some cooking time but it’s a fairly hands-off process, just some required stirring occasionally. Your stovetop does most of the work!

  1. Prep: Peel off the outer layer of the onions, cut the onions in half, then slice them thinly.
  2. Melt Butter: Heat the butter in a large skillet over medium heat.
  3. Start Sautéing: Add the onions and sauté for 5 minutes or until they start to soften.
  4. 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! Cooking time depends on the size of your onions and the temperature. Slow and low is best.
  5. Add Water: If the onions start to stick to the bottom of the pan, reduce the heat to low and add more water. Stir continuously to prevent burning.
  6. Serve: Enjoy as a topping or in various recipes!
6-photo collage of the onions being cut, added to a pan, and cooked until tender.

Quick Tips

Making caramelized onions is really simple, and will take dinner to the next level. Use these tips so they’re perfect every time!

  • What Pan to Use: I recommend a large skillet, so the onions have plenty of surface area and the water can evaporate, which helps with browning. A 10-inch skillet works great for up to 3 onions. Use a 12-inch or larger pan for 4 or more onions. Cast iron skillets and stainless steel pans will produce the best results. Nonstick pans and enameled cast iron can be used, but will slow down the caramelization process.
  • Type of Onion: I like to use yellow onions for the most balanced sweet and savory flavor. However, any variety of onion can be caramelized. White onions or red onions will offer a slightly different flavor, and Vidalia onions will become even sweeter, which may be too sweet for some recipes.
  • Heat Level: The key to perfectly deep golden brown caramelized onions is to cook them low and slow. This will ensure they have the best flavor and have a silky texture. You can adjust the flame or burner settings as needed while cooking.
  • Serving Suggestions: These are spectacular as a topping over pretty much any type of steak, pot roast or pizza! My family also loves them added to burgers, soups, pastas and dips! It’s a super versatile addition to many of your favorite meals.
Closeup of caramelized onions on a wooden spoon.

Storing Leftovers

Once you’ve made these mouth-watering onions, don’t let any leftovers go to waste! They can easily be stored and enjoyed later to add an irresistible umami taste to your meals.

  • In the Refrigerator: Store in an airtight container for 4-5 days. Reheat on the stove over medium-low heat when ready to serve. You can also pop them in the microwave to rewarm.
  • In the Freezer: Transfer your caramelized onions to a freezer bag or freezer-safe container, and store for up to 3 months. Thaw overnight in the fridge before you reheat them.
Caramelized onions added to a cheesy dip.

More Onion Recipes You’ll Love

Onions add such wonderful flavor to a variety of different recipes! Here are some of our best onion recipes that you will definitely love! From appetizers to main dishes, they are loaded with savory onion flavor that’s sure to have you coming back for seconds. If you have onions on hand that you don’t know what to do with, check out my full list of onion recipes here!