French Onion Soup

Ingredients

For the soup

• 4 tbsp unsalted butter, 56 g
• 3 lb yellow onions, 1.4 kg, about 6 large, thinly sliced
• 1 tsp fine salt
• 1 tsp granulated sugar, optional, to help browning
• 3 garlic cloves, finely chopped
• 2 tbsp all-purpose flour (plain flour)
• ¾ cup dry white wine, 180 ml
• 8 cups beef broth, 1.9 L
• 4 thyme sprigs
• 1 bay leaf
• 1 tbsp Worcestershire sauce
• ½ tsp black pepper

For the topping

• 6 slices baguette, about 1 inch (2.5 cm) thick
• 2 cups Gruyère cheese, 200 g, grated

Instructions

Caramelize the onions

1. Melt the butter in a large Dutch oven over medium heat. Add the onions and salt, cover and cook for 15 minutes, stirring occasionally, until soft and wilted.
2. Uncover, add the sugar and reduce the heat to medium-low. Cook for 45 to 60 minutes, stirring every few minutes and scraping the bottom, until the onions are deep golden brown and jammy. Add a splash of water whenever the bottom of the pot starts to darken.

Make the soup

3. Add the garlic and cook for 1 minute. Sprinkle in the flour and stir for 1 minute.
4. Pour in the wine and scrape up the browned bits. Simmer for 2 minutes.
5. Add the broth, thyme, bay leaf, Worcestershire sauce and pepper. Bring to a boil, then simmer gently for 25 to 30 minutes. Remove the herbs and taste for salt.

Gratinée

6. Heat the broiler (grill). Toast the baguette slices on a baking sheet until golden on both sides.
7. Set six oven-safe bowls on a baking sheet and ladle in the hot soup. Top each with a toast and a generous handful of Gruyère.
8. Broil for 2 to 4 minutes, until the cheese is melted, bubbling and browned in spots. Serve carefully; the bowls will be very hot.