Description
A classic French soup featuring deeply caramelized onions simmered in a rich beef broth, topped with toasted baguette croutons and melted Gruyère cheese. This comforting and savory soup is perfect for a cozy meal, showcasing the perfect balance of sweetness from the onions and the hearty flavor of melted cheese.
Ingredients
Soup
- 3 large onions, thinly sliced
- 2 tablespoons butter
- 1 tablespoon olive oil
- 1 teaspoon sugar
- 2 cloves garlic, minced
- 4 cups beef broth
- ½ cup dry white wine (optional)
- ½ teaspoon salt
- ¼ teaspoon black pepper
Croutons and Cheese
- 1 baguette, sliced
- 1 cup grated Gruyère cheese
- Fresh thyme (optional)
Instructions
- Heat Butter and Oil: Heat butter and olive oil in a large pot over medium heat to prepare for caramelizing the onions.
- Caramelize Onions: Add the thinly sliced onions to the pot and cook slowly over medium heat for 25–30 minutes, stirring occasionally, until they are deeply caramelized and golden brown.
- Add Sugar: Sprinkle in the sugar to help enhance the caramelization process and continue stirring until the onions develop a rich sweetness.
- Cook Garlic: Stir in the minced garlic and cook for about 1 minute until fragrant, taking care not to burn it.
- Deglaze with Wine: Pour in the dry white wine and let it simmer for 2 minutes to reduce slightly and allow the alcohol to cook off, adding depth of flavor.
- Add Broth and Seasoning: Pour in the beef broth, add salt and black pepper, then bring the soup to a simmer and cook for an additional 15 minutes to meld the flavors.
- Toast Baguette Slices: While the soup simmers, toast the baguette slices in the oven or under a broiler until they are crisp and golden brown.
- Assemble Soup: Ladle the hot soup into oven-safe bowls, place toasted baguette slices on top, and generously sprinkle grated Gruyère cheese over the croutons.
- Broil Cheese: Place the bowls under a preheated broiler for 2–3 minutes until the cheese melts and becomes bubbly and slightly golden.
- Garnish and Serve: Optionally garnish with fresh thyme sprigs and serve immediately while hot and cheesy.
Notes
- Gruyère cheese is traditional for this soup, but Swiss cheese or Emmental work as good substitutes.
- Slow cooking the onions over medium heat is critical for developing their rich caramel flavor; rushing this step can result in bitterness.
- White wine is optional but adds great depth and acidity to balance the sweetness of the onions.
- For a vegetarian version, substitute beef broth with high-quality vegetable broth.
- Bread slices should be well toasted to hold up under the hot soup and melted cheese.
- Prep Time: 15 minutes
- Cook Time: 45 minutes
- Category: Soup
- Method: Stovetop
- Cuisine: French
