Slow Cooker French Onion Soup

This Slow Cooker French Onion Soup is comfort food at it’s finest. Packed with all of the french onion flavor you love and cooked just right, you’ll love this topped with my bread and cheese, or plain as a light onion soup!

slow-cooker-french-onion-soup5It’s official, you are all loving Slow Cooker Sunday as much as I am! We started with Carne Asada, then moved onto Thai Curry Chicken. Both of which have been MAJOR hits with you lovely individuals! Don’t forget to keep on tagging me on Instagram when you make a dish!

I took a little poll on Snapchat earlier this week to see which recipe you guys wanted first. The choices were…

A. Pork Ragu

B. French Onion Soup

C. Short Rib Stew

D. Other

It was pretty close between the French Onion and Short Rib Stew, but don’t you worry, you’ll have both of them!

Slow Cooker French Onion Soup

You pile it allllllll in.

And then we’re going to cook those onions to perfection! 

Slow Cooker French Onion Soup

Slow Cooker French Onion Soup

Prep Time 15 min Cook Time 8 hr Yields 4



  • Place butter and oil in the bottom of your slow cooker insert.
  • Add in sliced onions, coconut sugar, garlic, balsamic vinegar, half the salt and pepper, thyme and bay leaves. Toss to coat and cook on low for 6 hours.
  • After 6 hours, add in beef broth, fish sauce, arrowroot flour, and the remaining salt and pepper.
  • Let cook for the remaining 2 hours. Remove bay leaves and thyme sprigs if using fresh thyme. Taste and add salt and pepper as desired.
  • Heat the oven to 350°F. Divide the soup between oven-safe bowls. Top each with a slice (or two) of toasted bread and sprinkle cheese in a thick layer over the bread and up to the edge of the bowl. Bake for 20 to 30 minutes until cheese is bubbling. Broil on high for 1 minute.
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Slow Cooker French Onion Soup

Slow Cooker French Onion Soup

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6 comments on “Slow Cooker French Onion Soup

  • Hi Lexi. This looks amazing! I’m wondering if I could use chicken stock instead. I don’t eat beef at all so I’m wondering if this substitution would work. What are your thoughts? Thanks!

  • This is delicious!!! I made this in my large slow cooker this past weekend. I let it cook for 14 hours or so and then had it the next day. I didn’t bother with the bread and cheese, and just ate it as it is. Loved it! Thank you!

  • Made this tonight. It’s was delicious! My husbands first time ever trying French onion soup and he loved it. Next time I may add a splash of red wine, but totally not necessary. Thanks for another great recipe!


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