Slow Cooker Onion Soup Recipe -
Slow Cooker Onion Soup Recipe
  • READY IN 4+ hrs

Slow Cooker Onion Soup

Recipe by  

"This is about the best onion soup I've been able to come up with. Tastes better than any restaurant onion soup I've ever had."

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Ingredients Edit and Save

Original recipe makes 3 servings Change Servings
  • PREP

    15 mins
  • COOK

    4 hrs 15 mins

    4 hrs 30 mins


  1. Melt butter in a skillet over medium heat; cook and stir sweet onion and red onion in melted butter until softened, about 10 minutes. Cook and stir garlic into onion mixture until fragrant, about 2 minutes. Transfer to a slow cooker.
  2. Pour beef stock, brandy, soy sauce, and Worcestershire sauce into slow cooker. Season with salt and black pepper.
  3. Cook soup on High for 4 to 5 hours.
  4. Preheat the oven's broiler and set the oven rack about 6 inches from the heat source.
  5. Ladle the soup into 3 oven-proof bowls; top with croutons and a slice of Provolone per bowl.
  6. Broil in the preheated oven until cheese melts and begins to brown, about 3 minutes.
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  • Easy Cleanup
  • Try using a liner in your slow cooker for easier cleanup.

Reviews More Reviews

May 20, 2012

Surprizingly good--even my husband, who is a french onion soup snob, liked it. I was surprized that a french onion soup could be this good from a crockpot. I used a quality brand beef stock, I added some fresh ground pepper when I sauteed the onions/garlic and I made my own homemade croutons. Next time, I think I would use all sweets and maybe add one more onion but that's honestly a personal preferance, not a reflection of the recipe. I'd make this again.

Aug 31, 2012

This was tasty! It was definitely easier than making onion soup the traditional way...I did feel that it was a bit on the thin side, though. I only used sweet onion and more than called for. The flavor was nice! This won't replace my usual onion soup recipe, but for quickness and ease, this was great! I may even try to use this method w/ my usual recipe, b/c the concept is just great. I made my own 'croutons', using sliced baguette that I toasted on each side and then rubbed w/ a clove of fresh garlic, and I used swiss just b/c that's what I always use when I make onion soup. All in all this was good and I would def make it again, with a few minor adjustments! Thanks for sharing. :)

Sep 23, 2012

Very good and rich.

Oct 15, 2013

I cooked this on low 8 hours over night, prep it & put it in the crock pot before I went to sleep. Just woke up to this & had to try it. More salt! I added 1/2 a tsp & it still needs more. I skipped the brandy & did 3 tbs of beef stock & it worked out perfect cause that's exactly what I had left of it. My husband wont even let me cook with alcohol pregnant, Ive explained to him it evaporates, still big no. It tastes a lot better with the croutons & cheese, it has a better flavor I think from the seasoning on the croutons. I didnt do the oven safe bowl & all that I just put it in the microwave for 1 serving for myself. Im going to see how this freezes, keeping the croutons & cheese seperate untill re-warming it. Its good, Im eating it as I write this. Definately not the onion soup from Mimi's cafe but still yummy. If I make this again I will use baugette as apposed to crouton & season the soup up a bit with some herbs.

Mar 26, 2013

I had this for lunch today. We had made it a few weeks ago and froze it (cheese, croutons, soup). Had I known it would be this amazing, I would have had some way before today!! LOL.... The best Onion Soup I ever had in my life (and I've had/made quite a few). Enjoy!!

Aug 11, 2014

Easy and delicious. I have made this several times. I have made it with both croutons and French bread, and surprisingly I prefer the croutons for the extra seasoning.

Apr 23, 2014

This was my first attempt at onion soup. I must say, I was very impressed! It's delicious! Only things I did differently was add a can of beef consumme, and cook it on low for 8 hours. I wouldn't recommend that if you only made the three serving recipe. I doubled it. The liquid reduced quite a bit while cooking. I also did not add salt or pepper. The soup is salty enough on it's own. This was a big hit at my house. I will make this again for sure… and often!

Jan 12, 2014

I am a huge fan of French onion soup. This is one of the best I've had! And soo easy to make


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  • Calories
  • 498 kcal
  • 25%
  • Carbohydrates
  • 30.6 g
  • 10%
  • Cholesterol
  • 62 mg
  • 21%
  • Fat
  • 29.3 g
  • 45%
  • Fiber
  • 3.3 g
  • 13%
  • Protein
  • 16.8 g
  • 34%
  • Sodium
  • 1044 mg
  • 42%

* Percent Daily Values are based on a 2,000 calorie diet.

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