# What You'll Need:
→ Onions
01 - 6 large yellow onions, thinly sliced
02 - 2 tablespoons unsalted butter
03 - 1 tablespoon olive oil
→ Broth
04 - 6 cups beef broth or vegetable broth for vegetarian option
05 - 1/2 cup dry white wine, optional
→ Flavorings
06 - 2 cloves garlic, minced
07 - 1 teaspoon granulated sugar
08 - 1 teaspoon salt
09 - 1/2 teaspoon freshly ground black pepper
10 - 2 sprigs fresh thyme or 1/2 teaspoon dried thyme
11 - 1 bay leaf
→ Topping
12 - 4 slices crusty French bread, approximately 1 inch thick
13 - 2 cups grated Gruyère cheese
# Method:
01 - In a large heavy-bottomed pot, melt butter with olive oil over medium heat. Add sliced onions and cook, stirring occasionally, until softened, approximately 15 minutes.
02 - Sprinkle onions with sugar and salt. Continue cooking, stirring frequently, until deeply golden and caramelized, 30 to 40 minutes.
03 - Add minced garlic and cook for 1 minute.
04 - Pour in white wine if using and scrape up browned bits from pot bottom. Simmer for 2 to 3 minutes.
05 - Add beef or vegetable broth, thyme, bay leaf, and black pepper. Bring to boil, then reduce heat and simmer uncovered for 30 minutes. Remove and discard thyme sprigs and bay leaf.
06 - Preheat broiler. Arrange bread slices on baking sheet and toast under broiler until lightly golden on both sides.
07 - Ladle hot soup into oven-safe bowls. Top each with toasted bread slice and generous handful of Gruyère cheese.
08 - Place bowls under broiler until cheese melts and bubbles, 2 to 3 minutes. Serve immediately.
