Ingredients
Soup Base
- 4 tablespoons unsalted butter
- 2 tablespoons olive oil
- 4 cups yellow onion, sliced
- 5 cups beef broth
- 2 tablespoons dry sherry
- 1 teaspoon dried thyme
- Salt, to taste
- Ground black pepper, to taste
Toppings
- 6 slices French bread
- 6 slices Provolone cheese
- 4 slices Swiss cheese, diced
- 1/4 cup grated Parmesan cheese
Instructions
- Sauté onions: Heat a Dutch oven or large pot over medium heat. Add unsalted butter and olive oil, stirring until the butter melts. Add sliced yellow onions and cook, stirring occasionally, until soft and translucent, about 8 to 10 minutes.
- Simmer soup: Pour in beef broth, dry sherry, and sprinkle dried thyme. Season with salt and black pepper to taste. Stir well and let the soup simmer on medium heat for 30 minutes to develop deep flavors.
- Prepare for broiling: Preheat your oven broiler to high. Ladle the hot soup into oven-safe ramekins. Top each with a slice of French bread, followed by a slice of provolone cheese and a few pieces of diced Swiss cheese. Finish by sprinkling grated Parmesan cheese over the top.
- Broil and serve: Place ramekins under the broiler for 2 to 3 minutes or until the cheese is golden brown and bubbly. Carefully remove from oven and serve immediately, optionally garnishing with freshly chopped parsley for added freshness and color.
Notes
- Use sliced yellow onions for the best sweetness and caramelization.
- Dry sherry adds a subtle depth; you can substitute with dry white wine if preferred.
- Broil the soup just until the cheese melts and browns—watch closely to prevent burning.
- Oven-safe ramekins are essential for broiling directly without transfer.
- To make the soup vegetarian, replace beef broth with a rich vegetable broth.
- Prep Time: 10 minutes
- Cook Time: 35 minutes
- Category: Soup
- Method: Stovetop
- Cuisine: French
