Crockpot Caramelized Onions

This post may contain affiliate links. Please read my disclosure policy.

Crockpot Caramelized Onions are the perfect addition to any meal! This slow cooker recipe makes the perfect topping for sandwiches, burgers and so much more!

caramelized onions slow cooker


Crockpot Caramelized Onions

I am so excited to share today’s recipe with you.  I love love love onions!!!  Much like butter, caramelizing makes everything better.  I did 2 crockpots of onions to finish off the last of the crate of onions that I got from a friend.  I have to admit, I ate them all myself in about two weeks.  I smothered them on everything.  Toast, sausage, hamburgers, burritos with chicken, burritos with cheese, just a caramelized onion burrito were all incredible with the caramelized onions.

I made these two different ways, just a minor change made such a huge difference.  The first batch I added 1 tablespoon of sugar (to get the caramelizing going) they were sooooo sweet.  Almost sickly sweet.  I contemplated making a corn bread to serve them with, I told my friend Mary that I thought they should go on a cake or something.

The second batch I omitted the sugar completely and they were perfect!  They were perfectly sweet and incredibly delicious.  Mr. W and Em did not partake in these delightful onions, partially because Chad doesn’t like onions, but mostly because I WAS NOT SHARING.


With love, from our simple kitchen to yours. 

crockpot caramelized onions in mason jar

Don’t miss a thing! Follow us on

Facebook Twitter Pinterest | Instagram 

Get Free Recipes Sent to Your Email

Do you ❤️ TSRI? Don’t miss another recipe!

Subscribe to The Slow Roasted Italian by email to receive new recipes in your inbox!!

Today is actually my Mommy’s birthday, and since we can’t be together I am hosting a virtual birthday party.  I love you Mommy!  Happy Birthday and I wish I could be with you in person today. You are a gift to our family and everyone who knows you – you have touched so many lives! We love you and count you as a blessing every day. Thank you for helping me become the woman, wife and mother I am today!  Have a beautiful Birthday!  XOXO


jar of slow cooker caramelized onions

Slow Cooker Caramelized Onions

Donna Elick
Slow Cooker Caramelized Onions are sweet, delicious, and so easy to make! Make a big batch for sandwiches, burgers, hot dogs, and more!
5 stars from 1 review
Tried this recipe?Please comment and review!
Prep Time 5 minutes
Cook Time 8 hours
Total Time 8 hours 5 minutes
Course Condiment
Cuisine American
Method Slow Cooker
Servings 4 make 2 cups



  • 8 large onions
  • 4 tablespoons butter, unsalted
  • 4 tablespoons extra virgin olive oil
  • pinch salt


  • Slice onions 1/4-1/2″ thick.
  • Add salt, butter and olive oil to crock pot.
  • Add as many onions to crock pot as you can fit. I could only fit about 3/4 of my onions originally, but added the rest as the onions reduced. Stir to combine. Keep crock pot uncovered as onions cook and reduce. Stir onions often scraping the sides.
  • After several hours onions are reduced, but still not caramelized.
  • Total cook time is approximately 6-8 hours. Remove onions once they are caramelized to your preferred taste, remove from crock pot. If they start burning and become incredibly aromatic, be sure to check them. Enjoy, they are so incredibly delicious. I am going to make another batch. Each batch makes approximately a pint of caramelized onions.


Serving: 1 | Calories: 344cal | Carbohydrates: 28g | Protein: 3g | Fat: 26g | Saturated Fat: 9g | Cholesterol: 30mg | Sodium: 102mg | Sugar: 13g | Fiber: 5g | Calcium: 73mg | Iron: 1mg

All nutritional information is based on third party calculations and is only an estimate. Each recipe’s nutritional value will vary depending on the ingredients used, measuring methods, and portion sizes.

Tried this recipe?Let us know how it was!

Originally Published Sep 20, 2011

The Simple Kitchen cookbook affiliate linked banner

Disclosure: Posts may contain affiliate links. If you purchase a product through an affiliate link your price will remain the same and The Slow Roasted Italian will automatically receive a small commission. Thank you for supporting us, it helps us keep creating new recipes.


  1. What a lovely idea! Happy Birthday Mommy! These onions look the best! and brilliantly helpful as they add a yum factor to just about anything!

  2. I bookmarked these on Mary's site and now seeing them again here makes me want to run out and get some onions. I am making these as soon as I get back from the store. I think its very interesting that you cook these with the cover off. Isn't it funny how a little bit of sugar makes onions sweet so quickly?

  3. Happy Birthday, Mom!
    Donna, these look just as delicious as they did on Mary's. I think it's a sign I'm supposed to get that crock pot out!

  4. I so need to make these! I love love love caramelized onions but they definitely take a ton of time over a hot stove…this seems like the perfect solution to that! 🙂

  5. i see that you have the onions shown in a mason jar–did you choose it simply for storage or did you have aspirations of preserving the onions for a later time?/is that possible?

  6. Its been a while since I had last tasted caramelized onions and I hadnt thought of it either. I am going to try that out 2morrow.

    thx for sharing!

  7. I am so doing this today!!

    Do you need more onions? I can have Miles take more to Mary's for you 🙂 I have plenty!!

  8. Yum Yum, I am in a crock pot mood and this will fit the bill nicely, I agree about omitting the sugar, what is it with people plonking heaps of white sugar into everything! I love the taste of onions! Thank you.. celi

  9. I just did this last night – on low all night long. I didn't salt them, and only used a couple tablespoons of olive oil. I will try it next time with a bit of butter – but they are fabulous with just the olive oil. made a nice big batch to bring to a cookout and they were a big hit. Will do this on a regular basis!

    1. I really don't know for sure. Mine are always devoured quickly. I would say that 2 weeks is about right though. Hope that helps!


    1. Hi Ruth! Cook them on high, but be sure to stir them every once in a while (every hour or two).

      Hope that helps!


  10. carimal is made with sugar…….maybe vidalia onions.?….please reply as i have 25 lbs. of these sweet onoins.:)

    1. The onions will become sweet without sugar. Trust me. If you add sugar, they will become more a dessert spread. That was with regular yellow onions, vidalia would be great too.

      Hope that helps.


    1. Hi Jean!

      Thanks for taking the time to leave a comment. I did not can these. It is my experience that it is not a good idea to can butter and these are made with butter. I would check with someone who is more of an authority on canning (I am not). I love canning jars and store condiments and such in the fridge in canning jars.

      Hope that helps!


    2. Put in freezer containers and freeze. I often do that with onions and mushrooms as I like them on steak and burgers.

  11. I had two crockpots. I cut up three bags of onions. Turned them on at 11:00AM and by 11:30PM they still weren't caramelized. I threw them in the fridge and the next day I finished them on the stove in batches. I'm thinking it might of took so long because I did so many. The final result was delicious though.

  12. I see that you said these would probably last about 2 weeks, I'm assuming that they would have to be refrigerated, since they have butter in them. Is that true?

Leave a Reply

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

Recipe Rating