# 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
15 - 1 cup Gruyère cheese, grated
# How to Prepare:
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, about 35-40 minutes. Add sugar and salt halfway through to enhance caramelization.
02 - Add minced garlic and cook for 1 minute until fragrant. Sprinkle in flour and stir constantly for 2 minutes to create a light roux.
03 - Pour white wine into the pot, scraping the bottom with a wooden spoon to release caramelized bits. Add stock, thyme sprigs, and bay leaf. Bring to a simmer over medium heat, then reduce heat and cook uncovered for 20-25 minutes.
04 - Remove thyme sprigs and bay leaf from the broth. Season with black pepper and additional salt to taste.
05 - Preheat oven broiler. Arrange baguette slices on a baking sheet, brush both sides with olive oil, and toast under the broiler for 1-2 minutes per side until golden brown.
06 - Ladle hot soup into oven-safe bowls. Top each bowl with one toasted baguette slice, then cover generously with grated Gruyère cheese. Place bowls on a baking sheet and broil for 2-3 minutes until cheese melts, bubbles, and turns golden brown.
07 - Remove bowls from broiler immediately and serve while hot.
