Slow Cooker Caramelized Onions

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Slow Cooker Caramelized Onions! No babysitting a pan and constantly stirring! Just onions, butter, and brown sugar cooked until meltingly sweet.

Slow Cooker Caramelized Onions in crockpot

Slow Cooker Caramelized Onions

Slow Cooker Caramelized Onions are a favorite kitchen hack of mine because they eliminate the never-ending babysitting that cooking caramelized onions require. They also make your whole kitchen smell fantastic, like you’re in a French restaurant about to be served a buttery French Onion Soup. Slow Cooker Caramelized Onions cook perfectly

Why Crockpot Caramelized Onions?

The process of cooking these Slow Cooker Caramelized Onions takes minutes compared to the old-fashioned way. The best part, (aside from not having to hover over them for an hour) is you can’t burn the bottom of the pot!

One of the most irritating things about cooking caramelized onions is if you neglect them for even a minute too long, you may start to burn the onions. Once those onions are burned, you can’t recover. The flavor of the burned onion will be immediately recognized and in case you need them for a dish that’s got a non BBQ flavor, you’re probably going to have to start over. Not so with crockpot caramelized onions.

Slow Cooker Caramelized Onions also manages to keep you from being up to your elbows in a giant pot of raw onions, cooking them until they start to break down (think spinach except it doesn’t melt down in less than a minute, it takes a solid ten minutes of stirring).

Crockpot Caramelized Onions requires no babysitting!

Tools Used In This Slow Cooker Caramelized Onions Recipe:

  • Slow Cooker: Love this slow cooker and how programmable it is, it has been a workhorse for me… until…
  • My New Slow Cooker: This recipe was made in this slow cooker. For larger roasts, I also brown the meat in the insert and not lose a bunch of the flavor by transferring the meat and leaving the browned bits behind. If you’re thinking of a new slow cooker, consider it if your budget is open.



Slow Cooker Caramelized Onions

4.67 from 3 votes
  • Yield: 12 servings
  • Prep Time: 10 minutes
  • Cook Time: 10 hours
  • Total Time: 10 hours 10 minutes
  • Course: Side
  • Cuisine: American
  • Author: Sabrina Snyder
Slow Cooker Caramelized Onions with no babysitting a pan and constantly stirring! Just onions, butter and brown sugar cook until meltingly sweet.


  • 6 yellow onions , thinly sliced
  • 4 tablespoons butter
  • 1 tablespoons brown sugar


Note: click on times in the instructions to start a kitchen timer while cooking.

  1. Add the butter and brown sugar to the slow cooker and top with the sliced onions.
  2. Cook on low for 10 hours.

  3. If too much liquid is in the slow cooker cook with the lid turned to the side to allow venting for an hour (if you catch it before it is done cooking for 10 hours go ahead and let it vent for the last couple of hours.

Nutrition Information

Yield: 12 servings, Amount per serving: 59 calories, Calories: 59g, Carbohydrates: 6g, Fat: 3g, Saturated Fat: 2g, Cholesterol: 10mg, Sodium: 35mg, Potassium: 80mg, Sugar: 3g, Vitamin A: 115g, Vitamin C: 4g, Calcium: 14g, Iron: 0.1g

All images and text © for Dinner, then Dessert.

Keyword: Slow Cooker Caramelized Onions

Crock pot full of Slow Cooker Caramelized Onions

Slow Cooker Caramelized Onions with no babysitting a pan and constantly stirring! Just onions, butter and brown sugar cook until meltingly sweet.
Slow Cooker Caramelized Onions with no babysitting a pan and constantly stirring! Just onions, butter and brown sugar cook until meltingly sweet.
Slow Cooker Caramelized Onions with no babysitting a pan and constantly stirring! Just onions, butter and brown sugar cook until meltingly sweet.

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  1. So yummy. I forgot the sugar but it didn’t miss it. I will be making these again and again. Next time I want to add some liquid smoke to see if that will have any effect on them. What I really like is that this is a perfect recipe for when you notice your onions are starting to take root in the veggie bin and you need to use them quick. So easy.

  2. I made these today and they are amazing! Followed recipe exactly with no issues. Will be doing this again and again. Thank you Sabrina for all your great recipes. You haven’t failed me yet. I love your site and greatly appreciate all the work you do and your generosity in sharing.

  3. how long do these delicious looking onions last in the fridge? and what type of container is best to store them in?

  4. These look so awesome, and I love that you’ve mentioned that they do well in the freezer. I’m just having trouble understanding step 3 of the recipe. Should I start with the lid propped to the side, or check on them partway through cooking and vent the lid only if there is too much liquid? How would I know if there is too much liquid? Thank you for the great recipe!

    1. The easiest way to explain the difference in how it can look is if it looks soupy then there’s too much liquid. You really want the liquid to be under the onions and not over it. If you have too much liquid, just prop the lid half way through. Hope this clears up any confusion!

  5. Is the sugar necessary? I have a few dietary restrictions and one is no sugar or substitutes. Natural Sweeteners only. I do use coconut sugar on occasion. Any suggestions?

    1. It aids in the browning of the onions, especially since you’re cooking on such a low heat. I’ve never personally cooked with coconut sugar so I can’t quite vouch for it, but if I were you I would probably stick to a more classic pot method for onions without the sugar. Low heat for a long time and naturally as the water evaporates the onions will caramelize. Sorry for the delay your comment accidentally ended up in the spam filter and I just saw it.

  6. I have never made caramelized onions in my slow cooker before but will definitely be doing it next time. I love how easy it is.

    1. Sorry this comment took so long to get to, it ended up in my spam filter somehow! Yes, absolutely! I have some in my deep freeze as I type this!

  7. I LOVE caramelized onions! This is such a great idea, thanks for the inspiration. I’m going to give this a go!

  8. I can just see these caramelized onions slathered on all sorts of yummy things. Burgers, sandwiches, and maybe in an omelette.

  9. I’m going to have to try this! It’s so hard to run after 2 toddlers and watch a pot of onions! Great tip!

  10. I’ve made caramelized onions countless times, but never in a slow cooker. I really need to give this method a try. So easy and no babysitting a pan.

  11. I regularly cook big batches of caramelized onions, but haven’t tried them in the slow cooker yet. I’ll definitely be doing this soon!