I love the flavor of caramelized onions, from French onion soup to burgers and more. What I don’t love, however, is standing over a stove stirring them for nearly an hour to get that real caramelized look. What if I told you we could make air fryer caramelized onions instead?
Will it still require some work? Of course. However, I find it’s less tending overall, which I’m all about.
Now you can whip up some caramelized onions anytime to top up some air fryer frozen hamburgers or anything else you’re in the mood for.
This was a total game changer for me, but try cooking kielbasa in the air fryer, and then use your caramelized onions on some pierogies!

Can I Caramelize Onions in an Air Fryer?
You can caramelize onions in the air fryer in that they will be browned, with a caramelization of the natural sugar in the onion.
However, they are not quite the same as a stovetop version. The onions won’t get “mushy” when cooked in the air fryer. Rather, they’re still browned, but more firm. I equate them to a more “leathery” texture, though they’re not tough per se.
Of course, if you really overcook them or raise the temperature up, then you’ll get super crispy onions (which are great, but not exactly what you’re looking for in a caramelized onion).

Either way, that doesn’t mean that air fryer caramelized onions are not still delicious! It’s a great alternative when you’re short on patience or time to watch your onions on the stove.
You may not make “traditional” French onion soup with them, but they go great in a microwave grilled cheese!
How to Make Air Fryer Caramelized Onions
- Preheat air fryer to 300°F following manufacturer guidelines

- Peel and slice an onion into about ¼” thick slices

- Separate and toss sliced onions with 1 Tbsp olive oil and 1 Tbsp melted butter or margarine

- Season with salt and pepper to taste

- Place sliced onions into preheated air fryer basket

- Cook on air fry setting for approximately 20-30 minutes at 300°F, stirring every 10 minutes
- Onions are done when they are soft and browned

I have a Ninja Foodi Dual Zone air fryer and it took 25 minutes in total to get the onions to the caramelized state here. However, times will vary slightly based on the brand and power of your air fryer.
Make sure to cook in smaller increments and check more frequently the closer they are to being done.
The reason I use 300°F here is to keep the temperature below the smoke point of butter (around 302°F). This allows you to cook the onions without burning them.
There’s no need to add sugar during the process, as onions have a lot of natural sweetness. However, if you want to add 1 Tbsp of brown sugar, it’s fine to do so in the last 5 minutes of cooking (to prevent burning the sugar).
I typically use a Spanish or Vidalia (sweet) onion. However, you can certainly use a red onion here as well if preferred.
If you love all things onion, make sure to check out how to make air fryer frozen onion rings for a quick and easy app or side!
Softer Air Fryer Caramelized Onions Tips
If you’re looking for something softer and closer to a traditional caramelized onion from your air fryer and have more time on your hands, you can achieve it by cooking them with foil.
- Slice your onion into ¼” thick slices
- Season with 1 Tbsp oil (olive), 1 Tbsp butter (or margarine), and salt and pepper
- Place the onions in an oven-safe dish or ramekins that fit in your air fryer basket
- Top dish with foil. Make sure to secure the foil around the container so it doesn’t blow open
- Air fry in a preheated air fryer at 300°F for an hour (no need to stir, just let it cook)
- Remove the foil and cook the onions for an additional 15 to 20 minutes at 300°F, stopping to stir every 5 minutes, until browned
The onions will basically steam and get soft in the foil-wrapped container, and then the final cooking steps will brown them up. The result is a softer (though still not “mushy”) caramelized onion.

I personally don’t think the time here is worth it over the traditional stovetop method. However, because it’s so low on effort once you set it to cook, it may be worthwhile for you.
Usually, I just do the shorter method seen in the recipe card below so I can get dinner done quicker!
Final Thoughts
While it’s not exactly the same as the stovetop, making air fryer caramelized onions is easy and requires a lot less tending. It’s not going to be the same as an hour of attentive cooking will get you, but it’s still delicious nonetheless.
These sautéed style caramelized onions in the air fryer are great for pasta dishes, sauces, soups, grilled cheese, burgers, hot dogs, and more.
If you love onions, make sure to check out my easy vinegar cucumber onion salad recipe.

Air Fryer Caramelized Onions – Perfectly Browned!
Equipment
- Cutting board
- Paring knife or similar
Ingredients
- 1 Large onion (yellow or sweet variety preferred)
- 1 Tbsp Olive oil
- 1 Tbsp Butter or margarine
- Salt & pepper (to taste)
Instructions
- Preheat air fryer to 300°F following manufacturer guidelines
- Peel and slice an onion into about ¼” thick slices using a paring knife or similar on a cutting board1 Large onion
- Toss sliced onions with 1 Tbsp olive oil and 1 Tbsp melted butter or margarine1 Tbsp Olive oil, 1 Tbsp Butter or margarine
- Season with salt and pepper to tasteSalt & pepper
- Place sliced onions into preheated air fryer basket, without overcrowding too much (a packed single layer is ideal)
- Cook on air fry setting for approximately 20-30 minutes at 300°F, stirring every 10 minutes. Add additional cooking time in 5-minute increments as needed
- Onions are done when they are soft and browned looking
Notes
- While yellow (pictured) or sweet (like Vidalia) onions are best for this, you can also use red onions with relative success
- One large onion generally makes between ¼ and ⅓ cup caramelized onions
- Salt and pepper is optional but recommended for flavoring. If you use salted butter, make sure to reduce the amount of other salt added
- No sugar addition is required since onions have natural sugars. However, if you want extra sweet onions, add 1 Tbsp brown sugar in the last 5 minutes of cooking to prevent burning
- Cooking at the lower temperature is important to prevent burning and over-crisping of onions (butter has a smoke point of 302 degrees)
- I have a Ninja Foodi Dual Zone air fryer and it took 25 minutes in total to get the onions to the carmelized state here. However, times will vary slightly based on the brand and power of your air fryer.
- If you have an oven-safe dish that fits in your air fryer basket, feel free to use that to hold the onions. It makes stirring and cleanup easier, and prevents onions from falling through the grate as they shrink from losing moisture (though may increase cooking time slightly as it will cut down air flow)
- Nutrition information will vary based on specific ingredients used, so please consider this a rough guideline only
Nutrition

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