# What You Need:
→ Vegetables
01 - 4 large yellow onions, thinly sliced
02 - 2 cloves garlic, minced
→ Liquids
03 - 6 cups vegetable broth
04 - 1/4 cup dry white wine, optional
→ Dairy
05 - 4 tablespoons unsalted butter
06 - 1.5 cups grated Gruyère cheese
07 - 1/4 cup grated Parmesan cheese
→ Breads
08 - 4 slices baguette, toasted
→ Herbs & Spices
09 - 1 teaspoon sugar
10 - Salt and freshly ground black pepper, to taste
11 - 1 teaspoon dried thyme
12 - 1 bay leaf
# Directions:
01 - Melt butter in a large saucepan set over medium heat. Add the sliced onions, sugar, and a pinch of salt. Cook, stirring frequently, until onions are soft and just beginning to caramelize, about 10 minutes.
02 - Stir in the minced garlic and sauté for 1 minute. Add dried thyme and bay leaf, mixing well.
03 - Pour in the dry white wine, if using, and let simmer for 2 minutes so the liquid slightly reduces. Add vegetable broth, increase heat, and bring mixture to a simmer. Cook uncovered for 10 minutes. Remove and discard the bay leaf. Season generously with salt and black pepper according to taste.
04 - Preheat broiler. Arrange baguette slices on a baking sheet and toast until golden brown.
05 - Ladle hot soup into broiler-safe bowls. Place a toasted baguette slice on top of each portion. Sprinkle each serving generously with Gruyère and Parmesan cheese.
06 - Position bowls under the broiler for 2 to 4 minutes, until cheese is melted and bubbling. Serve immediately while hot.