Learn how to caramelize onions on the stovetop with this easy step-by-step guide! While it takes some time to properly make caramelized onions, it’s super easy and the result is so delicious. Caramelized onions add so much flavor to soups, burgers and dips!

caramelized onions in bowl with fork

A magical thing happens when onions are slowly cooked to a beautiful golden brown. The natural sugars bring out an amazing sweetness while still being savory at the same time. 

Don’t be surprised if you end up making this caramelized onion recipe on a weekly basis, so they’re always in your fridge. They’re delicious added to sandwiches, steaks, eggs and so much more!

caramelized onions in bowl with fork

Ingredients

  • Butter – you will need some kind of fat to use in the pan. Butter has a great flavor and works really well, but you may also choose to use olive oil.
  • Onions – any onion variety such as sweet onions, yellow onions, vidalia onions, red onions, and white onions will caramelize well. Use a mix of multiple types of onions for a more complex flavor.
  • Salt – sea salt is recommended, so that it dusts over the onions evenly. Coarser grinds are not recommended.

How to cut onions for caramelizing

Onions can be sliced or diced to make caramelized onions. The classic method for making caramelized onions, calls for them to be sliced, which is what we’re going to do today.

If you’re making the caramelized onions for a burger and want diced onions instead, you can use the same method in this post, but simply dice the onions, instead of slicing them.

onion sliced on cutting board
knife cutting an onion on cutting board
slices of onion on cutting board
  1. To slice the onions, start by cutting the onion in half, then removing the stem of the onion. Use a sharp knife to slice the onion every 1/4 inch.
  2. Slice the other stem end of the onion off and discard.
  3. You now have perfectly even slices of onions.

It’s important that the onions used to make caramelized onions are evenly sliced, or they won’t cook at the same time.

sliced onion on cutting board

How to caramelize onions

Use the step-by-step guide and images below to help you make perfect caramelized onions at home, every time! For the full detailed recipe instructions and ingredient quantities, scroll to the recipe card at the bottom of this post.

butter melting in cast iron pot

Step 1: Place a heavy skillet on the stove over medium high heat and add butter.

sliced onions in pot on stove

Step 2: Once the butter is melted, add the onion slices to the skillet. Spread the onions out evenly in the skillet.

sliced onions cooking in pot on stove

Step 3: Cook for 5 minutes, sprinkle with salt, and reduce the heat down to medium.

sliced onions caramelizing in pot on stove

Step 4: Cook for 45 minutes, or until the onions are soft and browned. Only stirring every 10 minutes.

Use the onions immediately, or store in the refrigerator for up to one week.

Frequently asked questions

  • Can you use any color of onion to make caramelized onions? Any color of onion will work, and for even more depth of flavor, I recommend using a mix of different colors of onions.
  • How long does it take to caramelize onions? This will depend on how many onions you’re caramelizing, and how big your pot is, but plan for at least 45 minutes to properly caramelize the onions.
  • Do you use oil or butter to caramelize onions? You can use either, or both! I like the flavor of onions caramelized in butter, so I use 3 tablespoons butter, when caramelizing 3 pounds of onions. You can also use 1 1/2 tablespoons butter + 1 1/2 tablespoons oil, if you prefer.
  • Can you use vegetable oil to caramelize onions? Yes, you can use vegetable oil, canola oil or olive oil to make caramelized onions.
  • Do you add salt or sugar to caramelize onions? Salt is always a yes, sugar is a no for me. You need salt to help pull out the water in the onions. Otherwise, the onions will simply steam in the pot instead of caramelize. If you properly caramelize the onions using this recipe, they’re already very sweet, so I don’t feel like added sugar is needed.
  • Can you freeze caramelized onions? Yes, I recommend freezing them in an ice cube tray, or small containers, so that you can simply thaw only what you need for one recipe at a time. They will stay good in the freezer for up to 3 months. Thaw in the refrigerator overnight before using them in a recipe.
caramelized onions in red bowl with wooden fork

Tips and tricks

  • Always caramelize onions over medium heat, and keep an eye on them. There’s nothing worse than spending all the time to make caramelized onions, and then burning them! It takes a while to caramelize onions, so I know that the temptation is there to turn up the heat, but don’t do it! Just wait it out and keep an eye on them, stirring every 10 minutes during the caramelization process, so that you can make sure they’re never burning. You can also turn the stove down to medium low heat if they are cooking too fast.
  • If you ever feel like the onions are starting to burn at the bottom of the pan, turn the heat down slightly and deglaze the pan with 1-2 tablespoons of water. Use a spatula to scrape up any brown bits on the bottom and continue to watch the onions to make sure they don’t burn.
  • Always use a cast iron skillet, or dutch oven, when caramelizing onions. A cast iron skillet will get nice and hot, and maintain an even heat during the cooking process. If you don’t have a cast iron skillet, use the heaviest and largest pan you have available.
  • Use a pan that’s big enough for the onions to spread out. If the pan is too small and there’s too many onions in the pan, they’ll steam themselves, instead of caramelize and it will take much longer to cook the caramelized onions. For this recipe, which calls for 3 pounds of onions, I recommend at least a 12 inch skillet or dutch oven, or something bigger.
  • Only stir the onions every 10 minutes. Stirring them more than this will not allow them to brown and caramelize in the pan.
  • Never slice the onions less than 1/4 inch thick. Slicing onions too thinly will mean that they’re more likely to stick to the pan and burn. Using 1/8-1/4 inch thick slices will prevent them from drying out and burning during the caramelization process.
  • Every 1 pound of raw onions will equal approximately 1 cup of caramelized onions. If you only need 1 cup of caramelized onions, you only need to cook 1 pound of sliced, raw onions with 1 tablespoon butter, or olive oil.
french onion dip in bowl with wavy potato chips

How to serve them

There’s really not a wrong way to eat caramelized onions. They’re fantastic as a garnish or mixed in to so many recipes! Use these ideas to get you started.

caramelized onions on wooden fork coming out of a bowl

More kitchen tutorials

Don’t miss these other quick and easy kitchen how-to guides!

caramelized onions in bowl with fork
Print Recipe Pin Recipe
5 from 1 vote
Rate this Recipe

How To Caramelize Onions

Learn how to caramelize onions on the stovetop with this easy step-by-step guide! While it takes some time to properly make caramelized onions, it's super easy and the result is so delicious. Caramelized onions add so much flavor to soups, burgers and dips!

Ingredients

  • 3 tablespoons butter, or olive oil
  • 3 pounds onions, cut into ¼ inch slices
  • ½ teaspoon sea salt

Instructions

  • Add the butter (or olive oil) to a 12 inch (or larger) cast iron skillet on the stove over medium high heat.
  • Once the butter is melted, add the onions and spread them out evenly in the skillet.
  • Cook for 5 minutes, sprinkle the salt over the onions, then reduce the heat to medium.
  • Cook for 45-60 minutes, stirring every 10 minutes.
  • If the onions start to stick to the bottom of the pan, lower the heat to medium-low.
  • Use the onions immediately, or store in the refrigerator for up to one week.

Notes

  • Every 1 pound of raw onions will equal approximately 1 cup of caramelized onions.
  • Any color of onion will work for making caramelized onions. For even more depth of flavor, I recommend using a mix of different colors of onions.
  • Caramelized onions can be frozen for up to 3 months. I recommend freezing them in an ice cube tray, or small containers, so that you can simply thaw only what you need for one recipe at a time. Thaw in the refrigerator overnight before using them in a recipe.
  • Always caramelize onions over medium heat, and keep an eye on them. There’s nothing worse than spending all the time to make caramelized onions, and then burning them! It takes a while to caramelize onions, so I know that the temptation is there to turn up the heat, but don’t do it! Just wait it out and keep an eye on them, stirring every 10 minutes during the caramelization process, so that you can make sure they’re never burning. You can also turn the stove down to medium low heat if they are cooking too fast.
  • If you ever feel like the onions are starting to burn at the bottom of the pan, turn the heat down slightly and deglaze the pan with 1-2 tablespoons of water. Use a spatula to scrape up any brown bits on the bottom and continue to watch the onions to make sure they don’t burn.
  • Always use a cast iron skillet, or dutch oven, when caramelizing onions. A cast iron skillet will get nice and hot, and maintain an even heat during the cooking process. If you don’t have a cast iron skillet, use the heaviest and largest pan you have available.
  • Use a pan that’s big enough for the onions to spread out. If the pan is too small and there’s too many onions in the pan, they’ll steam themselves, instead of caramelize and it will take much longer to cook the caramelized onions. For this recipe, which calls for 3 pounds of onions, I recommend at least a 12 inch skillet or dutch oven, or something bigger.
  • Only stir the onions every 10 minutes. Stirring them more than this will not allow them to brown and caramelize in the pan.
  • Never slice the onions less than 1/4 inch thick. Slicing onions too thinly will mean that they’re more likely to stick to the pan and burn. Using 1/8-1/4 inch thick slices will prevent them from drying out and burning during the caramelization process.

Nutrition Facts

Calories 282kcal (14%)Carbohydrates 42g (14%)Protein 5g (10%)Fat 12g (18%)Saturated Fat 7g (35%)Polyunsaturated Fat 1gMonounsaturated Fat 3gTrans Fat 0.5gCholesterol 30mg (10%)Sodium 496mg (21%)Potassium 666mg (19%)Fiber 8g (32%)Sugar 19g (21%)Vitamin A 359mg (7%)Vitamin C 34mg (41%)Calcium 108mg (11%)Iron 1mg (6%)
Did you make this recipe?Tag @WhitneyBond on Instagram and hashtag it #WBRecipes!

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com.