# What You'll Need:
→ Onions
01 - 3 large yellow onions, thinly sliced
02 - 1 tablespoon unsalted butter
03 - 1 tablespoon olive oil
→ Soup Base
04 - 2 cloves garlic, minced
05 - 1 teaspoon sugar
06 - 1/2 teaspoon salt
07 - 1/4 teaspoon freshly ground black pepper
08 - 2 tablespoons all-purpose flour
09 - 1/2 cup dry white wine
10 - 5 cups beef or vegetable stock
11 - 2 sprigs fresh thyme
12 - 1 bay leaf
→ Topping
13 - 4 slices French baguette, about 1 inch thick
14 - 1 tablespoon olive oil for bread
15 - 1 cup Gruyère cheese, grated
# Method:
01 - In a large pot or Dutch oven, heat butter and olive oil over medium heat. Add sliced onions and stir to coat. Cook, stirring frequently, until onions are soft and deeply caramelized, approximately 35-40 minutes. Add sugar and salt halfway through to enhance caramelization.
02 - Add minced garlic and cook for 1 minute until fragrant.
03 - Sprinkle in flour and cook, stirring constantly, for 2 minutes to thicken the base slightly.
04 - Pour in white wine and scrape the bottom of the pot to release all browned bits and caramelized particles.
05 - Pour in stock and add thyme sprigs and bay leaf. Bring to a simmer, then reduce heat and cook uncovered for 20-25 minutes. Remove thyme and bay leaf. Season with pepper and adjust salt to taste.
06 - Preheat oven broiler. Arrange baguette slices on a baking sheet, brush both sides with olive oil, and toast under the broiler until golden, approximately 1-2 minutes per side.
07 - Ladle hot soup into oven-safe bowls. Top each bowl with a toasted baguette slice and cover generously with grated Gruyère cheese.
08 - Place bowls on a baking sheet and broil for 2-3 minutes until cheese is melted, bubbly, and golden brown. Serve immediately.
