Crock Pot Caramelized Onions

Well that was the easiest, least-messy batch of caramelized onions I’ve ever made — and I’ve caramelized a lot of onions in my time — on top of the stove, in an oven and on the grill.  But I don’t think I’ll bother to do them anywhere but my slow cooker anymore.  You have to check this out.

Julienne 6 medium-sized onions.  Add them to a crockpot, along with 1/4 cup butter, 1/4 cup olive oil, 3 sprigs of fresh thyme and 2 pinches of salt.

From here, you have the choice of low or high.  All of the other recipes I found online cooked the onions on low for 5-18 hours, depending on your crock pot.  I wanted caramelized onions for my pizza that night, and our slow cooker’s low is VERY LOW, so I decided to live dangerously.

My onions took 5.5 hours on high and required a little supervision.  Try to pile the onions in the centre without too many sticking to the sides of the pot, then stir every hour or two, a little more often towards the end.

If you’re going out for the day, or if you’re cooking them overnight, then set the slow cooker on low — the onions will burn on high unless you stir them occasionally.


And would you look at what you get?  The butter really helps develop that deep colour, so unless you need to go vegan, use a 50/50 mixture with olive oil.

Some reviews of other recipes complained about soggy onions, but I didn’t find that at all.  If there is too much moisture towards the end of the process, I suggest switching it to high if you’re not there already, and removing the lid for the last hour or so.


Once cool, you can store these babies in the fridge for a couple of weeks.  They won’t last that long, though, so I’m not worried about storage.  The only question is, how many onions can I fit in my slow cooker?  I ‘m going for 10 next time.

How do you use your caramelized onions?  Around here, we put them on pizza, in grilled cheese, on roasted chicken sandwiches, in beef stew, and, hypothetically, into a beer & cheese bread that may just save the world.  I’ll let you know how that goes next week.

27 thoughts on “Crock Pot Caramelized Onions

    1. Theresa Post author

      Tamar — I didn`t even think of French Onion soup! I`m sure you could just pour the stock on top of the onions and continue the soup in the slow cooker…Theresa

  1. Stephanie

    Caramelizing onions isn’t really my favorite thing but the results area always worth it. I would love to put everything in my slow cooker and let it do the work for me! Thanks for sharing!

  2. Lee Ann

    How exciting to find this post! I’m definitely going to try this! I make my own “healthy” version of green-bean casserole…using caramelized onions instead of the processed fried ones…and this would make it even easier!!!

  3. Kath

    I have heard of making caramelized onions in a slow cooker, but have never tried it. I like your tip about cooking it on high without the lid for the last hour. I may have to try this soon!

  4. Stephanie @ Dollop of Cream

    It’s true — there’s something about caramelizing onions that makes them taste a whole letter better than the long, dreary process on stove! Thank you for this slow cooker recipe — I love the idea that I could just walk away from them (on low, I know!) for hours and they’d be ready when I come back.

    We love to put caramelized onions with roasted tomatoes and asiago in grilled sandwiches. The original recipe is from the Ace Bakery in Toronto and it’s possibly my favourite sandwich ever.

  5. Pingback: In the Box — CSA Week 13 {Summer Squash Lasagna} | Jax House

  6. Suzie the Foodie

    You were absolutely right, you can make them in the crockpot and thank you so much for the inspiration! I wrote a post about it today and you may have just saved me from bringing my crockpot to the thrift store.

  7. Pingback: Claire’s Spoon Bread from Drums of Autumn « Outlander Kitchen

  8. Pingback: caramelized onions | Diary of a Crazed Cook

  9. Pingback: Slow Cooker Caramalized Onions | MetaCookbook

  10. Kathryn

    Got 9 big onions in my pot right now. I took both of the times and combined them. Cooked on high first three hours then kicked it down to low for four hours. It added two extra hours but I didn’t babysit them during the last hours. Which I was afraid I have to do on high.

  11. Pingback: Claire's Spoon Bread from Drums of Autumn - Outlander Kitchen

Leave a Reply

Your email address will not be published. Required fields are marked *