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Illustrate the bowls of soup topped with thyme croutons and slices of Swiss cheese. The bowls are under the broiler, with the cheese melting and bubbling to a golden perfection. The finished soup is steaming and ready to serve.

Keto French Onion Soup Recipe

This classic French onion soup boasts caramelized onions in a rich, savory broth, topped with thyme-crusted croutons and gooey melted cheese. A comforting, hearty dish perfect for any occasion!
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Prep Time 15 minutes
Cook Time 1 hour 20 minutes
Total Time 1 hour 35 minutes
Course Soup
Cuisine French
Servings 8
Calories 418 kcal

Equipment

  • Large saucepan or stockpot
  • Wooden Spoon or Spatula
  • Knife and Cutting Board
  • Oven-proof soup bowls
  • Baking sheet
  • Parchment paper
  • Broiler or Oven

Ingredients
  

For the soup:

  • 3 tablespoons olive oil
  • 2 tablespoons butter
  • 4 cups thinly sliced yellow onions
  • 1 teaspoon kosher salt
  • 1/2 teaspoon ground black pepper
  • 1 teaspoon minced garlic
  • 1/3 cup dry white wine
  • 1 tablespoon fresh thyme leaves or 1 teaspoon dried
  • 3 bay leaves
  • 2 cups water
  • 8 cups beef stock or vegetable stock for vegetarian
  • 1 tablespoon Worcestershire sauce or for gluten free & vegetarian
  • 1 tablespoon granulated erythritol
  • 8 slices Swiss or Gruyere cheese to serve

For the toppers:

  • 1 batch Easy Keto Dough
  • 2 tablespoons fresh thyme leaves or 1 bunch of thyme springs

Instructions
 

For the Soup:

  • Heat oil and butter in a saucepan over low-medium heat. Add onions, salt, and pepper, and cook for 30 minutes until golden brown.
    Show a saucepan on the white marble cooktop, with olive oil and butter bubbling inside. Thinly sliced onions are being sautéed, starting to turn golden brown. A wooden spoon rests in the pan, ready for stirring.
  • Stir in garlic and cook for 2–3 minutes.
  • Add wine, thyme, and bay leaves. Simmer for 5 minutes until reduced by half.
    Illustrate the saucepan on the white marble cooktop, with golden onions, minced garlic, white wine, thyme sprigs, and bay leaves gently simmering. Steam rises from the fragrant mixture, which is slightly reduced.
  • Add water, beef stock, Worcestershire sauce, and erythritol. Simmer uncovered for 30 minutes. Remove bay leaves and adjust seasoning.
    Show the saucepan now filled with beef stock, water, Worcestershire sauce, and erythritol. The soup is simmering uncovered, with light steam rising. A ladle is placed beside the pot, ready for serving

For the Toppers:

  • Preheat oven to 375°F. Shape dough into 8 discs, press thyme leaves on top, and bake for 15 minutes until golden.
    Depict a baking tray on the white marble cooktop holding 8 discs of keto dough. Fresh thyme leaves are being pressed into the dough, with the tray ready for baking in a preheated oven.

To Assemble:

  • Ladle hot soup into oven-proof bowls. Top with thyme croutons and cheese slices.
    Illustrate the bowls of soup topped with thyme croutons and slices of Swiss cheese. The bowls are under the broiler, with the cheese melting and bubbling to a golden perfection. The finished soup is steaming and ready to serve.
  • Broil for 2–3 minutes until the cheese melts and turns golden. Serve hot.