Classic French Onion Soup (Soupe à l'Oignon)

Ingredients

• 4 large yellow onions, thinly sliced
• 4 tbsp unsalted butter
• 1 tbsp olive oil
• 1/2 tsp salt
• 1 tsp sugar
• 2 cloves garlic, minced
• 1/2 cup dry white wine or dry sherry
• 6 cups beef stock
• 1 tbsp fresh thyme leaves
• 1 bay leaf
• Salt and pepper
• For serving: thick baguette slices · 1.5 cups Gruyère, grated

Instructions

1. 1

   Melt butter and oil in a large heavy pot over medium heat. Add onions and salt. Cook, stirring occasionally, for 45–60 minutes until very deeply caramelized and amber. Add sugar halfway through to help browning. Do not rush this step.

2. 2

   Add garlic; cook 1 minute. Add wine and scrape up any browned bits. Cook until wine evaporates.

3. 3

   Add stock, thyme, and bay leaf. Simmer 20 minutes. Remove bay leaf. Season with salt and pepper.

4. 4

   Toast baguette slices under the broiler.

5. 5

   Ladle soup into oven-safe bowls. Top with toasted bread and a generous heap of Gruyère.

6. 6

   Broil until cheese is melted, bubbly, and golden, about 3–4 minutes. Serve immediately.