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How to Caramelize Onions

Have you ever wanted to know how to caramelize onions but haven’t known where to begin? You’re in the right place!

Bringing your onions to that perfect deep brown color with a sweet taste doesn’t need to be complicated. Continue reading to learn tricks and tips of how to caramelize onions perfectly each and every time!

A closeup of caramelized onions on a mound of rice. How to Caramelize Onions.

Why Caramelize Over Saute?

The big difference between sauteed and caramelized onions is taste. This is achieved with how long you cook your onions and at what temperature.

Caramelized onions are considerably sweeter and add a perfect touch to various meals. Sauteed onions retain the distinct onion flavor and bite, making them suitable for more savory-focused dishes.

Closeup of sauteed onions in a skillet.
Sauteed onions are translucent and slightly browned.

The most difficult part of caramelizing onions is having patience. It takes time and attention to allow these to cook properly and to your desired doneness. Do not raise the temperature on your stove in hopes that these will cook faster. You will simply cause them to burn and not caramelize properly.

Choose the Right Onion

Before you begin caramelizing onions, you’ll want to be sure you choose the right kind! While all onions will work, there are a couple that will give the best taste for your purposes.

Yellow onions work best for a more balanced flavor. Using yellow onions will give you a greater variety of recipes in which you can include your caramelized onions.

Closeup of whole yellow onions.

Vidalia onions will work too, but beware that they are already sweet and will only gain in sweetness once they’re caramelized. If you aren’t looking for an overwhelmingly sweet dish, you might want to skip using the Vidalia onion.

Prep Your Onions

There are several ways you can prepare your onions. Most any way you cut them will ultimately work. However, the French-cut version of preparing your onions is the suggested way to begin.

Onions being French cut into slices.

To do this, first, halve the onion from the root to the stem end. Next, cut a V-notch formation on the root end, removing the root piece.

Set one half of the onion with the flat side down on the cutting board, with the root end facing you. Then slice the onion length-wise from one side to the other, slicing it approximately in ⅛” thickness.

Repeat until all of the onions are sliced.

Use the Proper Skillet

Another consideration is the skillet you’ll be using to caramelize onions.

Use a large skillet so the onions can spread out and cook evenly. This allows the water to evaporate, allowing the onions to caramelize and not steam.

A non-stick pan won’t work as well as a cast-iron skillet. It’s necessary for the formation of a fond, which are browned bits of onion that stick to the bottom of the pan. A non-stick pan may prevent this.

Once the fonds form, you’ll use a wooden spoon to stir and scrape the pan, adding dark brown, crispy bits to the final product.

How to Caramelize Onions


Begin with gathering your ingredients! Decide which type of onion you want to work with. You’ll want 2-3 medium-sized onions of your choice.

You’ll also want to grab some extra virgin olive oil, salt, and sugar.


1. Slice your onions according to the method you wish to slice them. Set them aside.

Closeup of sliced onions.

2. Heat your cast iron skillet over medium heat. Add 2 tablespoons extra virgin olive oil and heat through.

3. Reduce the heat to low. Add enough onions to cover the bottom of the pan. Sprinkle 1-2 pinches of salt on top and stir the onions to mix well. Cook these until they are slightly translucent.

4. Add another layer of onions, repeating the above process. Continue to repeat these steps until all of the onions have been added to the pan.

Onions added to oil in cast iron pan.

5. Sprinkle 1 teaspoon of sugar over all of the onions and stir once more to mix evenly.

6. Continue to cook the onions for 15 minutes to 1 hour, depending on what kind of caramelization you prefer.

Cooking Guide

Cooking your onions for 15-20 minutes will turn them to a blonde color. These onions are considered sauteed and will still have a bit of an onion bite. They are perfect for making soups.

Onions cooked to the saute stage.
Onions at the saute stage.

Cooking your onions for 30-40 minutes will turn them to a golden brown color. These onions will be softer and are good for adding to grilled cheese sandwiches or quiches.

Onions cooked beyond a saute, but not yet to the caramelized stage.
Onions between sauteed and caramelized.

Cooking your onions for 45-60 minutes will turn them to a dark brown color. These onions will have crisp edges with crusty fond pieces. These onions are great for topping burgers or steaks.

Fully caramelized onions on rice.
Fully caramelized onions.

Tip: If at any time the onions start to stick and burn to the pan without easily scraping with a wooden spoon, add a splash of water or broth to loosen them.

Deglaze Your Skillet

Once you’ve finished caramelizing your onions, deglaze the pan by adding ¼ cup of water, broth, cooking wine, brandy, or balsamic vinegar to the pan and scraping the bottom.

This will help clean your pan before the remainder bits dry and stick to the pan. It will also prepare your cast iron skillet for storage.

How to Serve Your Caramelized Onions

There are endless ways to serve your caramelized onions! These yummy onions are good enough to eat by themselves. Or add them to one of these dishes to add a sweet and powerful punch to your meal!

A steaming crock of onion soup au gratin.
Onion soup.


Caramelized onions will make your next sandwich a hit! Try serving them on your grilled cheese sandwiches, cheesesteaks, patty melts, or your other favorite toasted sub.

Not sure where to begin? Try this French Melt Sandwich recipe to get you started!


Eggs are a great way to add any sort of vegetable! Toss these yummy caramelized onions into your scrambled eggs, frittata, or your next omelet to add some flavor.

Impress your family and friends with this fancy Parmesan and Caramelized Onions Egg Toast dish!


Another versatile way to use your caramelized onions is with pasta! Top your preferred pasta with your caramelized onions and sauce.

Or try this delicious Caramelized Onion and Garlic Pasta recipe!


Homemade pizza.

Top your favorite pizza with your caramelized onions! You can’t go wrong when you add these pre-cooked onions that will add a kick of sweetness to your pizza. Be sure to load up on your other favorite toppings to round out this supper!


Of course, soups make a great way to show off your caramelized onions. French onion soup, bean soup, or tomato soup are great places to begin when adding a little extra flavor.

For a traditional French Onion Soup recipe, try this one along with a bit of crusty bread!

Eat Your Caramelized Onions Tonight!

Caramelized onions on rice.

That’s everything you need to know about how to caramelize onions. They aren’t hard to make, as long as you have patience and you’re willing to keep an eye on your skillet!

How will you serve your caramelized onions for your next meal?

For more information about the different varieties of onions to use in your kitchen, visit our Onions page!