Slow Cooker Caramelized Onions are hands-off, rich, and perfectly sweet. No stirring, no babysitting, just effortless flavor!
The Slow Cooker does all the work for you! You literally just set it and walk away while it creates rich, hands-off flavor! Try making Bacon Blue Cheese Caramelized Onion Tart or the Easiest Brisket with Caramelized Onions.
Sabrina’s Slow Cooker Caramelized Onions Recipe
Slow Cooker Caramelized Onions are a favorite kitchen hack of mine because they eliminate the never-ending babysitting that cooking caramelized onions requires. They also make your whole kitchen smell fantastic, like you’re in a French restaurant enjoying buttery French Onion Soup.
Recipe Card
Ingredients
- 6 yellow onions , thinly sliced
- 4 tablespoons butter
- 1 tablespoons brown sugar
Instructions
- Add the butter and brown sugar to the slow cooker and top with the sliced onions.
- Cook on low for 10 hours.
- 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
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About this Recipe
One of the most challenging things about cooking caramelized onions is that 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.
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These photos were in a previous version of this post
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.
I’m so glad you enjoyed the recipe. Thanks for the 5 stars.
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.
That’s so sweet of you to say! I’m happy you’re loving the site and the recipes.
how long do these delicious looking onions last in the fridge? and what type of container is best to store them in?
They last about 3-4 days in the fridge in an air tight container.
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!
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!
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?
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.
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.
Can you freeze these after it is made?
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!
Caramelized onions are something we love to cook with as well. LOVE the idea of a slow cooker!
I LOVE caramelized onions! This is such a great idea, thanks for the inspiration. I’m going to give this a go!
I can just see these caramelized onions slathered on all sorts of yummy things. Burgers, sandwiches, and maybe in an omelette.
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!
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.
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!