How To Caramelize Onions

Caramelized onions in a white bowl.

Everyone should know how to caramelize onions at home. It’s a simple process that yields big results. You can use caramelized onions to top steaks, toss with sauteed vegetables, and take pizzas and sandwiches to the next level. This recipe is easy to follow, and they’re ready to use in under an hour.

Transforming eye-stinging alliums into a sweet, jammy condiment is like kitchen magic. It’s easy to do, takes less than an hour and will elevate your cooking game.

These slow-cooked onions are one of my favorite extras. They add a subtle complex sweetness to everything from French onion soup to French Dip sandwiches.

I use caramelized onion for burgers and garnishing pizzas, but you’ll find plenty of uses in your everyday cooking.

Newsletter Signup
Join our community of food lovers!

Get my latest recipes, helpful kitchen tips and more good things each week in your inbox.

Why you’ll love this recipe

  • It’s a delicious condiment that works with many recipes.
  • This recipe is easy and foolproof.
  • Even people who don’t like onions love them when caramelized.
  • You can make them in advance.
  • Double or triple the recipe; you’ll just need a large enough pot.
  • This recipe freezes well so that you can have them anytime.

Ingredients you’ll need:

Onions, butter and salt.
  • Onions – you can use any kind of onion for this recipe, from yellow to red, white, Vidalia, or a combination.
  • Butter – to help with caramelization and browning. I prefer unsalted butter and augment it with a pinch of salt. You can also use olive oil. However, I’ve found that butter does a better job of browning and bringing out the natural sugars in the onions.
  • Kosher Salt — just enough for wilting the onions and seasoning them.

How to caramelize onions (step-by-step instructions):

Slicing onions on a cutting board.
  1. Slice the tip off of the alliums and peel them. Cut off the root end and cut them lengthwise from root to tip in ¼”-½” slices.
Heat the pot over medium heat and melt the butter.

2. Place a heavy-bottomed pot or Dutch oven over medium heat and heat until the pot is hot. Add the butter to melt.

Adding sliced onions to the Dutch oven.

3. Add the slices and sprinkle with kosher salt. Cover the pot to seal and cook for 5 minutes without lifting the lid or stirring.

Stir the onions.

4. After 5 minutes, lift the lid and stir, scraping any stuck bits off the bottom of the pot. There may be parts that start to brown (a good thing), but more importantly, the sealed pot will begin to steam and wilt the onions.

The onions start to soften and turn a soft gold color.

5. Cover the pot and cook for 3-4 more minutes, then lift the pot and stir. More steam and concentrated cooking will begin to brown the vegetables in the butter as they soften and mellow.

After 20 minutes of cooking, the onions are softening and browning.

6. Continue to cook them in this fashion, letting them cook with the lid on for 4-5 minutes, then stirring and scraping the bottom of the pan.

Remove the lid from the pan and continue to cook stirring regularly.

7. After 25-30 minutes, remove the lid from the pot and stir more frequently to promote evaporation and browning. Use the spoon to scrape up any browned bits at the bottom of the pot or Dutch oven.

Once the liquid has evaporated, the onions are soft and golden brown - ready for use.

8. Once the excess liquid has evaporated and the veg is golden, soft and sweet, they’re ready to use.

Cooking Tips:

  • Use a heavy-bottomed pot or Dutch oven with a tight-fitting lid. Dutch ovens are made of cast iron and usually have a smooth enamel coating. The heavy pot maintains an even heat without hot spots, which is ideal for caramelizing onions.  You can also use a heavy stainless steel skillet with 3-4″ high sides and a lid.
  • Monitor your heat. All stoves are different, so it’s important to be able to read yours. If it runs very hot, you may want to keep the heat low or medium-low during the caramelization process.
  • The tight lid ensures that the alliums sweat and steam at the onset so that they cook down quickly. Salt also draws out moisture, helping them sweat and reduce faster.
  • If you have hot spots on your stove or your pot isn’t the best, you may need to stir more frequently to prevent scorching. Pay attention.
  • If they get too brown or start to scorch, deglaze with a tablespoon of water or broth and stir it in to loosen any stuck-on bits.
Caramelized onions in a cast iron pot (Dutch oven).

After the onions are caramelized you can add other seasonings to take them in one direction or another.


  • Add a few dashes of Worcestershire sauce for a more savory flavor – great for caramelized onions on burgers.
  • For sweetness, add a teaspoon or two of brown sugar.
  • Add a sprig of fresh thyme, sage or rosemary as they’re caramelizing.
  • Stir in 2-3 teaspoons of balsamic vinegar for more depth and a little tangy component.
Serving a bowl of caramelized onions.

Storage and Freezing:

Storage: You can keep sweet onions in an airtight container in the refrigerator for up to 10 days.

Freezing: You can freeze them in smaller, portioned containers for up to two to three months. I buy ¼ to ½ cup freezer containers to freeze the sweet alliums and keep them on hand for last-minute recipes.

Alternatively, you can also freeze them in ice cube trays and store them in zip-top baggies.

Ways to use this caramelized onion recipe:

  • Add the sweet onions to pasta in casseroles and bakes or stir them into tomato sauces to soften the acidity.
  • Top your grilled cheese sandwiches with a spoonful before griddling.
  • Make homemade caramelized onion dip with sour cream, mayo, and a dash of Worcestershire.
  • Dress up frozen peas with ¼ cup of caramelized onions.

More onion recipes to try:

Tried this recipe? Leave a rating and review.

Your comments and shares are invaluable to me and the thousands of readers who use this site daily. If you've made the recipe, leave a star rating and review. We want to hear how you liked it.

We'd love it if you shared the recipe with your friends on social media!

A white bowl of caramelized onions with a spoon on the side.
Print Pin
5 from 4 votes

How To Caramelize Onions

Always keep caramelized onions on hand by making them in large batches and freezing in ¼ cup or ½ cup containers.
Author: Lisa Lotts
Course Side Dish
Cuisine American
Keyword onions
Dietary Restrictions Dairy-Free, Egg Free, Gluten-Free, keto, Low-Carb, Paleo, Vegan
Prep Time 10 minutes
Cook Time 2 hours
Total Time 2 hours 10 minutes
Servings 8


  • 1 Dutch oven or heavy pot with a tight fitting lid


  • 3 pounds onions I used 4 large yellow onions
  • 3 tablespoons butter
  • 1 teaspoon kosher salt


  • Slice the root and tip off 3 pounds onions and peel. Slice the onions from root to tip in ¼ to ⅓” slices.
  • Heat the dutch oven over medium heat until the pot is hot. Add 3 tablespoons butter, which should melt and bubble when it hits the pot. Add the onions and 1 teaspoon kosher salt. Place the lid tightly on the pot and cook for about 5 minutes to jump start the onions into steaming and browning.
  • Stir the onions with a wooden spoon, scraping at the bottom to dislodge any cooked on bits. Return the lid to the pot and cook for 4-5 minutes and stir.
  • Continue in this manner of stirring, scraping and covering the pot for another 20-25 minutes or until the onions are soft and golden but still giving off their liquid in the pot.
  • Remove the lid to promote evaporation and stir every 2-3 minutes, scraping up any stuck bits from the bottom of the pot. Pay attention. If the heat is too hot, it will cook quickly and you risk burning the onions. Adjust the heat lower if necessary.
  • Continue cooking until the liquid has evaporated and the onions take on a deep golden hue. The onions should be so tender that they almost fall apart and should be sweet to taste.


You can portion the caramelized onions into storage containers to freeze so you’ve always got some on hand for use in your favorite recipes. 


Calories: 105.68kcal | Carbohydrates: 15.89g | Protein: 1.92g | Fat: 4.43g | Saturated Fat: 2.77g | Polyunsaturated Fat: 0.19g | Monounsaturated Fat: 1.13g | Trans Fat: 0.17g | Cholesterol: 11.29mg | Sodium: 331.25mg | Potassium: 249.66mg | Fiber: 2.89g | Sugar: 7.22g | Vitamin A: 134.6IU | Vitamin C: 12.59mg | Calcium: 40.56mg | Iron: 0.36mg

Pin It For Later!

A Pinterest Pin to save for later.

Leave a Reply

Your email address will not be published. Required fields are marked *

Recipe Rating

This site uses Akismet to reduce spam. Learn how your comment data is processed.


  1. I’m making these for french dip sandwiches. Is there a point in the recipe where you remove the lid, or do you leave it on the whole time?

    1. You’ll remove the lid to stir the onions, but it should be kept on for most of the time.

  2. Rita Chapman says:

    I would like to use these onions with garlic to add to steamed cabbage and carrots. I am making this recipe for 100 people.

    1. That’s a lot of people! You should be able to use garlic… but I would add it after the onions start to soften. You’ll need boatloads of onions for that many folks!

  3. I’ve tried to caramelize onions once before but it was a disaster. Thanks to your recipe, this task seems so manageable! Does this goes only for yellow onions or I can use also white ones?

    1. I’ve never done it with white onions, but I don’t see why it wouldn’t work with them as well. You could probably use red onions as well.

  4. 5 stars
    Learning how to properly caramelize onions was a game changer for me in the kitchen. I love to do it on fall days. And you’re right – low and slow is best! I’ve honestly never frozen them before. Do they retain their yumminess?

    1. They absolutely do! I’ve found little quarter cup plastic containers that I use for freezing. It’s just the right amount of onions for a few omelettes or burgers or whatever…

  5. 5 stars
    I do love the rich flavors that are pulled from caramelized onions. They can make a simple dish absolutely fabulous. I have never made them in advance and frozen them, hadn’t even thought about it… great idea.

  6. This looks mouthwatering! I have the Dutch oven and can get the onions, just need the patience. I can’t wait to make these. Maybe tonight! What a great idea to make them ahead of time and freeze.