Slow Cooker Caramelized Onions, cooked on high for 5 hours. Just mix yellow onions, butter, sugar and salt in a crockpot and come back to delicious buttery sweet caramelized onions! Freeze in ice cube trays to keep them for months. Save this recipe if you are growing onions in your garden!
Slow Cooker Caramelized Onions
What’s not to love about sweet caramelized onions made in the slow cooker? They are so delicious and can be added to practically any meal. Even better, they are so easy to make! It’s as simple as chopping onions into slices, throwing them in the crockpot with butter, sugar and salt, closing the lid… and you’re done!
We grow lots of onions in our garden so this is one of our favorite ways to preserve them. After they are cooked in the crockpot, we transfer to ice cube trays and freeze.
Caramelized onions take 5-6 hours on HIGH in the crockpot. This recipe makes approximately 2-3 cups of caramelized onions.
Need them quicker? Try my Quick Caramelized Red Onions. Looking for more yellow onion recipes? Check out my Onion Sandwich, Fried Corn and Onions, Homemade Onion Powder and Bangers and Mash with Beef Onion Gravy. For red onions, check out my Red Onion Jam and Red Onion Chutney!
Best onions for caramelizing
Yellow onions tend to be sweeter so they’re best for caramelizing. We grow “candy” yellow onions in the garden which have a rich sweet flavor.
Ingredients
- Yellow onions, 3 pounds, peeled and sliced. You can adjust this recipe if you have more or less onions.
- Butter, melted
- Salt
- Sugar
How To Make Caramelized Onions in the Crockpot
This recipe calls for 3 pounds of sliced onions. I use my 6 quart Slow Cooker and the onions take up about 75% of the space when they begin. Peeling and slicing 3 pounds of onions is tough business so if you have sensitive eyes like me I suggest wearing sunglasses while doing this and opening a window if you live in an apartment.
Add all of the ingredients into a large slow cooker and stir so the butter coats the onions.
Cook on HIGH until the onions are soft. For me this usually takes 5 hours.
Serve with your favorite dish or freeze the onions for later (directions below). So easy, right?
Freezing Caramelized Onions
Freezing caramelized onions is our main way to preserve them. Allow to cool and then place in ice cube trays to freeze. Once frozen, pop them out and then throw them in a freezer bag to freeze.
When ready to use them, grab a couple cubes out of the bag and defrost in the microwave.
Caramelized onions will last 6-8 months in the freezer.
Pin for later:
Slow Cooker Caramelized Onions (with Yellow Onions!)
PrintIngredients
- 3 pounds yellow onions peeled and sliced
- 1/2 cup melted butter
- 1 teaspoon salt
- 1 teaspoon sugar
Instructions
- Add everything into a large slow cooker and stir so the butter coats the onions completely.
- Cook on high for 5-6 hours or until onions become soft and caramelized. My slow cooker usually takes 5 hours.
- Serve with your favorite dish, store in the refrigerator for a few days or freeze to preserve. To freeze, allow to cool and then place in ice cube trays and freeze. When frozen, pop them out of tray and place in freezer bags to freeze. Defrost as you need them. Frozen caramelized onions can last 6-8 months.
Matthew says
We have too many onions and this is a great way to save them for later.
Steve Warren says
The secret to tear free onion slicing is a very sharp knife.
I start with a small serrated edged paring knife to top and tail the onions,
then placing a now flat end on the cutting board, I slice the onion in half with a thin bladed small japanese cleaver – which I also use to slice the onions.
Next I slip my thumb under the outer layer of the onion (inside the brown skin which may slip off anyway) and pry this layer off and discard it because it is often tough, sometimes a bit green and cooking doesn’t usually compensate for that.
Then I place the onion half flat side down and slice away with the very sharp knife – and hardly ever get teary eyed. Well, not from cutting onions anyway!
Pamela says
Hey Steve, thanks for sharing your tips!
Nisha @ Honey What's Cooking says
OMG ,these look insanely good! Just wow.
[email protected] says
This is genius! You have changed the way I will caramelize my onions forever!
Cheyanne @ No Spoon Necessary says
I have a serious obsession with caramelized onions. Like, I will make VATS of the stuff, because i want to be able to eat it by serving spoon full and still have enough left over to use it in actual dishes. But, I’ve never tried making it in the slow cooker! For some reason I didn’t think it would turn out well, but obviously it does because yours looks amazing!!! SOOOO DOING THIS! Cheers, girl!
Anu - My Ginger Garlic Kitchen says
Caramelized onions in a slow cooker for real? This sounds like a genius idea. Would love to try this recipe.
Amy (Savory Moments) says
This is a terrific idea! It would be perfect for making all the onions for French onion soup ahead of time.
Angie@Angie's Recipes says
Didn’t even know that you can make caramelized onions in slow cooker…so cool! Definitely give this a try.
Sues says
Oh yum!! I’ve never thought to caramelize onions in my slow cooker, but this is such an awesome idea!! I bet my kitchen would smell soooo delicious 🙂
Kayle (The Cooking Actress) says
ooooh I love caramelized onions too–my knees would probably also buckle 😛