Make fuss-free caramelized onions in your slow cooker or Instant Pot. No more standing over a stove stirring onions!

Table of Contents
ToggleWhat Are Caramelized Onions?
Caramelization is when sugar is browned to produce a dark brown color and nut flavor. Onions have natural sugars so if you cook them slowly over a long period of time, the natural sugars will caramelize. The end result is flavorful onions that can eaten as-is or reused in other recipes.

Why Make Caramelized Onions In The Slow Cooker or Instant Pot
The main reason to make caramelized onions in your slow cooker or pressure cooker is because it’s so easy! The traditional way to make caramelized onions involves standing over a stove constantly stirring the onions so they don’t burn. Here you just let the appliance do the work. There’s pluses & minuses to using either one. Using the slow cooker in particular makes it truly set it & forget it. I like to start mine at night so come morning the onions are ready to go. For the Instant Pot (pressure cooker), there’s an additional step or two but it cooks a lot faster than the slow cooker.

What Type Of Onions To Use
The good news is that you can use your preferred onion whether it be white, yellow, or even red. All onions caramelize. I used white onions because they were on sale at the grocery store this week.
Other recipes you might enjoy:
Use These Onions In Recipes
Sky is the limit when it comes to using caramelized onions. Of course you can eat them straight up by themselves. Most people will add them to foods like hamburgers, pizzas, sandwiches or even salads to add extra flavor. If you’re looking for a use, these onions are great in my low-carb/keto French onion soup recipe.
Slow Cooker – Cooking Off The Excess Liquid
Onions release natural juices while cooking and when you use your slow cooker the liquid has no where to evaporate. As a result, over the course of the first 7-9 hours, you’ll notice the onions will be sitting in a small pool of liquid. Don’t worry, you can easily cook this off. Around the 9-hour mark, place the lid to the slow cooker slightly ajar. Let the lid remain this way for the last few hours of slow cooking to evaporate the excess liquid off the onions. Or you can just wait and strain the liquid from the onions with a slotted spoon. For the electric pressure cooker, you will have to manually drain the excess liquid as explained below.
Instant Pot – Straining The Excess Liquid
First off, if you make this in your Instant Pot, it takes a heck of a lot less time to cook. Forget 10 hours, it’s done in less than 20 minutes. But there’s slightly more work than if you were to make the caramelized onions in the slow cooker. After the electric pressure cooker as pressurized and cooked the onions, you will need to strain the excess liquid and then return the onions to the pressure cooker and saute them until they’re caramelized to your liking.
I use a 3.5-quart slow cooker and a 6-quart Instant Pot (the only size I have) for this recipe.
{VIDEO} Slow Cooker/Instant Pot Caramelized Onions
5 Stars 4 Stars 3 Stars 2 Stars 1 Star
3.6 from 5 reviews
- Author: Fit SlowCooker Queen
- Prep Time: 10 minutes
- Cook Time: 12 hours
- Total Time: 12 hours 10 minutes
- Yield: Approximately 1 1/2 cups 1x
Ingredients
- 2 pounds onions, sliced
- 2 tablespoons olive oil or melted butter
- Pinch salt
Instructions
- Add the onions to the slow cooker. Add oil or butter and salt. Toss until onions are evenly coated.
- Cook LOW 10-12 hours.
- Season with salt to your liking.
Optional step: Around the 9-hour mark, place the lid to the slow cooker slightly ajar. Let the lid remain this way for the last few hours of slow cooking to evaporate the excess liquid off the onions.
- Add onions and oil/butter to the pressure cooker.
- Close lid and seal valve. Set manual, high pressure to 5 minutes. When done, quick release pressure.
- Strain liquid from onions. Add onions back to the pressure cooker. Turn on the sauté mode and cook the onions, stirring constantly, until they’re caramelized, approx 5 minutes.
- Season with salt to your liking.
Notes
Refrigerate covered for up to 5 days or freeze for up to 3 months.
This recipe is for plain-Jane basic caramelized onions. You can add in ingredients like a tsp of balsamic vinegar or brown sugar.
Nutrition
- Serving Size:
- Calories: 151
- Sugar: 9.6 g
- Fat: 7.2 g
- Saturated Fat: 1.1 g
- Carbohydrates: 21.2 g
- Fiber: 3.9 g
- Protein: 2.5 g
- Cholesterol: 0 mg
This post contains affiliate links, which means I receive money if you make a purchase using one of the links. For more about my disclosure policy see here: https://fitslowcookerqueen.com/about/disclosure-policy/
[adthrive-in-post-video-player video-id=”mn4sGZTk” upload-date=”2019-12-16T00:42:35.000Z” name=”Slow Cooker Caramelized Onions” description=”Make fuss-free caramelized onions in your slow cooker or electric pressure cooker (Instant Pot). No more standing over a stove stirring onions!” player-type=”static”]








5 thoughts on “Slow Cooker Caramelized Onions + VIDEO”
I made mine in the crockpot. Sliced up 6 (small to larger) Yellow Onions and added the 2 Tbl of Oiive Oil & Pinch of Salt. Cooked on Low for 6 hours. I didn’t cook off the extra liquid ( forgot I read that part 7 hours earlier. Lol.) Final amount was 1-1/2 cups of tender browned onions but a lot of liquid. I plan on draining and pan frying with a little butter when I need some tomorrow. Next time, I’ll cook it off. Actually, I’m saving the juice to add to a
Bowl of veggies.
If I can add a photo, the picture will show a pristine insert, because I used a crock pot cooking bag (happy choice! )
Definitely happy with the results. Thank you.
Followed the instapot recipe and the onions never caramelized to that deep golden color. Not even after 20 min of sauteing. Definitely will try someone else’s instructions next time, this was a waste.
It seems that this instant pot recipe is wrong. I followed it exactly (olive oil version) the onions were sliced thinly and evenly, the instant pot was put on maual at high pressure for 5 min, as everyone knows it takes 15 min to come to pressure, then the 5 mins of cooking, I let the instant pot do natural release as I went out to grab something from the store, when I returned I drained the onions and then turned on sauté, my instant pot does sauté for 30 mins, and it turned off before the onions even turned brown
… they are now a very light brown after the second sauté of 30 mins, so in total more time than on the stove top.
Tried the instant pot recipe! I didn’t like the idea of having to drain liquid from a steaming hot instant pot so I ended up just sautéing the onions longer (about 15 minutes) and they turned out great!
This looks really easy- cant wait to try this!