Slow Cooker Caramelized Onions
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Slow cooker caramelized onions – for those times when you don’t want to spend an hour caramelizing them on the stovetop – these cook while you sleep!
About this recipe
- Sweet and delicious: I’m head-over-heels in love with caramelized onions. They’re like candy, so sweet and flavorful.
- Hands-off: When it comes to making caramelized onions, I’m often hindered by the fact that they take a good 45 minutes to an hour to prepare, with some amount of babysitting and monitoring. This recipe is much more hands-off. If you want to try them the traditional way, check out our caramelized onion recipe.
- Large Batch: This recipe makes about 4 cups. Caramelized onions store well and can be frozen.
Tips for Success
Since the slow cooker traps a lot of moisture, after you cook these overnight you’ll wake up with a soupy onion mixture. Here are your two options:
- Continue to cook for 3-5 hours with the lid ajar to evaporate some of the liquid.
- Drain them and be done with it.
I continued to cook my slow cooker caramelized onions for about 5 hours more to achieve a nice thick consistency, almost jam-like. I’m really super happy with the result! Disclaimer – they’re not 100% the same, so if you’re a purist, this recipe might not be for you.
How to use caramelized onions
- I used these onions for baked chimichangas and you can’t tell the difference one bit. They are delicious topping this homemade French onion dip.
- Make your own crostini and top with spread with soft goat cheese and onions.
- Spread them on your sandwiches. Try them in ham and cheese sliders.
- Top turkey burgers with cheese, caramelized onions, and your sauce of choice. So good! You might also want to try air fryer burgers.
- Top grilled meat with the onions. Bonus points if you add sautéed mushrooms! Try marinating the chicken with balsamic marinade. You might also like pork chops with balsamic caramelized onions.
More Onion Recipes
I love it when onions play a starring role in a recipe, don’t you? Here’s a few more recipes that you might like:
- Vidalia onion tart with bacon, kale, and feta
- How to pickle red onions (so easy!)
- Homemade onion soup mix
Did you make this? Be sure to leave a review below and tag me @rachelcooksblog on Facebook, Instagram, or Pinterest!
Ingredients
- 8-10 onions, sliced in half moons
- 2 tablespoons unsalted butter
- 1 tablespoon olive oil
Instructions
- Add all ingredients to a slow cooker. Cook on low for 10 hours (I do it overnight).
- If desired, cook for another 3-5 hours with the lid ajar to evaporate the extra liquid and thicken the onions. This will also result in a darker, sweeter onion. If you’re in a rush, drain the extra liquid from the onions.
- Store covered in fridge for 4-5 days or freeze for up to 4 months.
Notes
- Makes about 4 cups.
Nutrition Information
This website provides approximate nutrition information for convenience and as a courtesy only. Nutrition data is gathered primarily from the USDA Food Composition Database, whenever available, or otherwise other online calculators.
Highwaygirl YYZ says
Wow, great idea! Going to definitely try this one.
I have an auto heat feature on my slow cooker that cooks on high for a few hours and then switches to low heat. Wondering if this may help cut down on cooking time (start them in the morning for use that night)…
Rachel Gurk says
I think that would work well! I don’t have a setting for that, but I do that often with slow cooker recipes.
Christine @ WRY TOAST says
are caramelized onions not the total best!?! love this low-maintainence way of preparing them, this is a keeper Rach! xo
DessertForTwo says
This is GENIUS. Where has this been my whole life?
Kayle (The Cooking Actress) says
ahhhh how I loooove caramelized onions!!!!!
Medha says
These look amazing! Such a hands-off way to get great flavor :)
denise says
sounds great
JessB says
Good idea! I love them too but never go to the work of making them-problem solved.
Alicia J. says
This recipe couldn’t have come at a more perfect time. I just received a 50 pound bag of fresh from the Georgia ground Vidalia onions. I had no idea how I was going to use the last 25 pounds I wasn’t able to hand out to my family. I know what I’m doing with them now. Thank you so much for this recipe. I can’t wait to get them cooked.