Delicious Slow Cooker French Onion Soup Recipe

4 stars
3.79 (14)
Delicious Slow Cooker French Onion Soup Recipe
Prep Time:
20 mins
Cook Time:
240 mins
Total Time:
Recipe by Administrator
Published on April 17, 2024

This Slow Cooker French Onion Soup is a comfort food classic made easy. Savory caramelized onions, rich beef broth, and cheesy toasted bread come together in this hearty dish that's perfect for a cozy night in. Let your slow cooker do all the work while you enjoy the delicious aroma filling your home.


  • 6 large yellow onions, thinly sliced
  • 4 tablespoons butter
  • 2 tablespoons olive oil
  • 2 teaspoons sugar
  • 1 teaspoon salt
  • 1/2 teaspoon black pepper
  • 2 cloves garlic, minced
  • 1/2 cup dry white wine
  • 8 cups beef broth
  • 2 sprigs fresh thyme
  • 1 bay leaf
  • 1 French baguette, sliced
  • 2 cups grated Gruyere cheese


  1. In a slow cooker, combine onions, butter, olive oil, sugar, salt, and pepper. Cook on low for 10-12 hours, stirring occasionally.
  2. Add garlic and white wine, and cook for an additional 30 minutes.
  3. Stir in beef broth, thyme, and bay leaf. Cook on low for another 6-8 hours.
  4. Preheat broiler. Ladle soup into oven-safe bowls and top with baguette slices and Gruyere cheese.
  5. Broil until cheese is melted and bubbly, about 2-3 minutes. Serve hot.

Interesting Facts

  • French Onion Soup dates back to Roman times when onions were easy to grow and affordable.
  • The slow cooking process brings out the natural sweetness of the onions, making them caramelized and flavorful.
  • Gruyere cheese is a traditional choice for French Onion Soup because of its nutty flavor and melting properties.