Traditional French Onion Soup

Instructions

1. Caramelize the onions
   In a large heavy-bottomed pot or Dutch oven, melt butter with olive oil over medium-low heat. Add the sliced onions and stir to coat with the butter mixture. Cover and cook for about 15 minutes until the onions are softened and translucent.
2. Develop the flavor
   Uncover, increase heat to medium, and add sugar to help with caramelization. Cook onions for about 40-45 minutes, stirring frequently, until they are deeply browned. Be patient, as proper caramelization takes time and is crucial for the soup's flavor.
3. Create the base
   Add minced garlic and cook for 1 minute until fragrant. Sprinkle flour over the onions and stir continuously for 2-3 minutes to cook the flour. Gradually add the beef stock while stirring to prevent lumps. Add the white wine, bay leaf, and thyme.
4. Simmer the soup
   Bring the soup to a simmer, then reduce heat to low. Cover partially and simmer gently for about 30 minutes, allowing the flavors to meld together. Season with salt and pepper to taste.
5. Prepare the bread
   While the soup is simmering, preheat the oven to 350°F (175°C). Place the baguette slices on a baking sheet and toast in the oven for about 10 minutes, until lightly browned and crisp.
6. Assemble and broil
   Preheat the broiler. Ladle the hot soup into oven-safe bowls placed on a baking sheet. Float 1-2 toasted baguette slices on top of each bowl of soup, then cover generously with grated Gruyère cheese. Broil for 2-3 minutes, until the cheese is melted, bubbly, and golden brown.