Slow Cooker French Onion Soup

READY IN: 5hrs
Recipe by Sageca

I made this fantastic recipe for a big batch of onion soup that You can freeze in portions to use later. Serve this with a lovely red wine and salad and voilà for a romantic meal. These are 14 large servings so if you are serving this before a meal reduce the amount of soup in your bowl.

Top Review by DeniseMB

This is perfect as written. Made the full recipe (just fit in a 6 qt. slow cooker) and I'll be lucky if I get to freeze half. ;) Been looking for the perfect FO soup recipe and now I've found it - a plus being less complicated than others I've tried - thanks!

Ingredients Nutrition


  1. Over medium heat sauté the onion in butter until soft and translucent and caramel colour. Make this in 3 batches.
  2. Place onions in slow cooker.
  3. Deglaze cooking skillet with some of the beef stock;this is the secret to that taste.
  4. Add to slow cooker along with the remaining beef broth (your own homemade or powdered mixed with boiling water).
  5. Add Worcestershire sauce, thyme and bay leaf.
  6. Cover; cook on High for 4 hours or on low for 6-8 hours.
  7. Add salt and pepper to taste. Remove bay leaf.
  8. Divide soup into appropriate containers.
  9. Seal and freeze.
  10. When ready to enjoy your French Onion Soup.
  11. Remove from freezer and place in a microwave dish with 2 tbsp sherry; heat for 5 minutes.
  12. Add Parmesan cheese to your onion soup bowl. Place one slice of toasted bread over the cheese. Fill bowl with soup.
  13. Top with shredded Gruyère cheese.
  14. Place under broiler to melt your cheese.
  15. Tip: When adding your ingredients to the slow cooker make sure they are all hot.
  16. Use the processor to slice your onions. I once read 'If I use my food processor just to make onion soup it will be worth the cost".
  17. Bon Appettit!

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