Classic French Onion Soup

1.In a large, heavy-bottomed pot, melt the butter with the olive oil over medium heat.

2.Add the sliced onions and sugar to the pot. Stir to coat the onions in the butter and oil.

3.Cook the onions, stirring occasionally, for about 25-30 minutes, until they are deeply caramelized and golden brown.

4.Pour in the white wine to deglaze the pot, scraping up any browned bits from the bottom.

5.Add the beef stock, bay leaves, and thyme to the pot. Bring the soup to a simmer.

6.Reduce the heat to low and let the soup simmer for 30-40 minutes to allow the flavors to meld.

7.Season the soup with salt and freshly ground black pepper to taste.

8.While the soup is simmering, preheat your oven to 350°F (175°C).

9.Arrange the baguette slices on a baking sheet and toast them in the oven for about 10 minutes, until they are crisp and lightly golden.

10.Once the soup has finished simmering, remove the bay leaves and ladle the soup into oven-safe bowls.

11.Place a toasted baguette slice on top of each bowl of soup and generously sprinkle with grated Gruyère cheese.

12.Place the bowls on a baking sheet and transfer to the oven. Broil for 3-5 minutes, or until the cheese is bubbly and golden brown.

13.Carefully remove the bowls from the oven and let them cool slightly before serving.