Slow-Cooker French Onion Soup

Add to My Favorites
My Favorites page is currently unavailable.

Add to My Favorites

Added to My Favorites


In this genius slow-cooker soup recipe, two types of onions are caramelized for hours before adding a sherry-spiked broth. For a bistro-worthy presentation, ladle the soup into ovenproof crocks, top with the bread and cheese and broil.

Prep/Cook Time: 8½ Hours, Servings: 8



  • 2 tablespoons butter, cut into 8 pieces
  • 2 tablespoons extra-virgin olive oil
  • 8 sprigs fresh thyme
  • 4 cloves garlic, smashed
  • 1 bay leaf
  • 2 pounds yellow onions, halved and sliced
  • 2 pounds red onions, halved and sliced
  • 1 teaspoon salt
  • ¾ teaspoon ground pepper
  • 4 cups low-sodium beef broth
  • ¼ cup dry sherry

Cheese Toasts

  • 8 diagonal slices baguette (1/2-inch-thick), toasted
  • 1 cup shredded Gruyère or Swiss cheese


  1. To prepare soup: Scatter butter in a 6- to 7-quart slow cooker. Add oil, thyme, garlic and bay leaf, then onions. Sprinkle with salt and pepper. Cover and cook on High for 8 hours.
  2. Bring broth and sherry to a boil in a saucepan. Remove the thyme sprigs and bay leaf from the slow cooker. Pour in the broth and cook on High, uncovered, for 10 minutes.
  3. To prepare cheese toasts: Meanwhile, position rack in upper third of oven; preheat broiler to high. Top each baguette slice with 2 tablespoons cheese. Broil until the cheese is melted, 1 to 2 minutes. Divide the soup among 8 bowls. Top each with a cheese toast.

© Dotdash Meredith. All rights reserved. Used with permission.