Air Fryer Onions (Caramelized or Sautéed)

Quickly cook up some caramelized onions in your air fryer. Easy to cook to exactly your liking, these onions are rich, sweet and delicious!

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Air fried caramelized onions served in a small blue bowl.

Last Updated on February 1, 2022 by Betty Davies

Cook up the most delicious onions in your air fryer with zero effort with this easy and flavor loaded recipe. Perfect to top burgers and hot dogs and use in other favorite recipes, it’s easy to cook these onions exactly how you want them, whether lightly sautéed or rich and caramelized.

Overhead shot of air fryer caramelized onions in a small serving bowl with a fork.

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Ditch your skillet and your stovetop, and cook up the most delicious sliced onions effortlessly with your air fryer.

This recipe makes it so easy to cook your onions exactly to your tastes, whether lightly sautéed to include in a larger meal, or deeply caramelized to use a a topping for burgers and hot dogs.

The air fryer onions are wonderfully sweet and rich and they have the most delicious depth of flavor, thanks to a little butter and brown sugar. They cook perfectly evenly and are so tasty that you can eat them right out of the bowl!

Be sure to try my Sautéed Zucchini and Onions and Whole Roasted Onions too!

Why you will love this recipe!

Quicker: Making caramelized onions is a bit of a labor of love, and to get those rich deep colors and flavors can easily take up to an hour. These are ready to use in less than 30 minutes, and a light saute is also much quicker.
Clean up is so much easier: The onions are cooked in a small baking dish that can easily be thrown quickly into the dish washer, rather than cooking them in your cast iron skillet which needs a little more love and care.
So delicious: Cook the onions in the air fryer doesn’t compromise on flavor at all. They are so rich, this is one addictive veggie dish!
Dietary info: These caramelized onions are gluten-free and vegetarian.

Ingredients

Onions: A large sweet onion like a Vidalia or a Walla Walla are perfect for caramelizing, but pretty much any will work great in this recipe.
Oil: Oil helps the onions to cook evenly. Any high heat neutral oil like avocado, vegetable or canola will work well.
Salt and pepper: To season the onions and enhance the flavor.
Brown sugar: The molasses in the brown sugar adds a complex sweetness and helps the onions to caramelize and get that deep rich brown color.
Butter: A little salted butter helps to add a wonderful texture and enhance the flavors even more.

How to cook onions in an air fryer

Be sure to scroll down for the full recipe!

Slice the onions and mix with the oil and seasonings (photo 1).
Top with butter and place in the air fryer (photo 2).
Cook, stirring occasionally, til the onions are done to your needs (photo 3).

Three step by step photos to show how to make the recipe.

Recipe Variations

Honestly, as they are, these air fryer onions, as they are come out so good, they are seriously the best! If you like, you could add in some diced garlic, or use an additional seasoning like Worcestershire sauce or some steak seasoning.

If you don’t have brown sugar, you can use white, but half the amount as it is much sweeter. I like to add the brown sugar for a deep sweetness, but you can omit it if you prefer.

To make these vegan, and a little healthier, you can skip the butter if you prefer.

Frequently Asked Questions

Can you caramelize red onions?

Absolutely! This recipe will work great with red onions and the process and timings remains the same. Cook some up to use in my red onion dip or red onion gravy!

What temperature do you cook onions in the air fryer?

Caramelizing or sautéing onions using the air fryer uses a similar process as if you were cooking the in a skillet on the stovetop. You start them at a high temperature to soften them, then continue on a lower heat so that they slowly caramelize.

At first, cook the onions at 400F for 8 minutes, after this time they will be lightly sauteed and good to use. For caramelization, turn the heat down to 360F and cook for up to 20 minutes, stirring every five minutes, til you get your desired doneness.

What do you cook them in?

Because the onions are sliced, it’s best not to add them straight into the basket in the air fryer, instead use an ovenproof baking dish that is heat resistant up to 420F. I used my 7.5 inch Staub casserole dish that fits perfectly in my 6qt basket air fryer.

Caramelized onions in a red baking dish garnished with fresh parsley.

Make ahead and storage

Once cooked, these onions will keep well for up to 4 days. Let them cool, then cover and refrigerate. The fats from the onions will solidify, but you can pop the dish straight into the air fryer and reheat at 360F for 3 to 4 minutes, stirring halfway through, and they will come together nicely.

Serving Suggestions

These air fryer caramelized onions have so many uses!

Serve them on hot dogs, burgers and sliders.
Add as a topping for pizzas.
Stir into pasta dishes.
Add to bruschetta with some goats cheese for a tasty appetizer.
Cook into a frittata.
Add to warm salads.
Add to a grilled cheese.

Recipe Notes and Tips

Make sure that the onion slices are well coated in the oil and seasonings. I like to use my hands to toss them so they are evenly covered.
Preheat the air fryer before adding the onions. If your air fryer doesn’t have a preheat function, let it run for 400F before adding them in.
Give the onions a quick stir every 5 minutes. This will help them to cook evenly and not dry out. I like to set my air fryer in 5 minute intervals so that I get a warning when I need to stir.
Different air fryer models can vary in their speed of cooking, so times may vary.

Cooked onion slices garnished with some parsley.

It’s so easy to make the most perfect caramelized onions in the air fryer. The flavors are seriously so good and wonderful deep and rich, I just know you are going to love these!

More Air Fryer Side Dishes

If you’ve tried this recipe, be sure to leave a star rating and a comment below!