Melt the butter in a large pot over medium heat. Add the sliced onions and cook until they are caramelized and golden brown, about 25-30 minutes, stirring frequently.

Deglaze the Pot

Pour in the white wine and scrape any browned bits from the bottom of the pot. Let it simmer for about 5 minutes.

Add Broth and Herbs

Add the beef broth, thyme, bay leaves, salt, and pepper. Bring to a boil, then reduce heat and let simmer for 30 minutes.

Prepare the Bread

While the soup is simmering, preheat your oven to 400°F (200°C). Slice the French bread and toast it in the oven until golden.

Serve the Soup

Remove the bay leaves from the soup. Ladle the soup into bowls, top with toasted bread and sprinkle gruyère cheese on top. Place under the broiler until the cheese is melted and bubbly.

For the Shrimp Cocktail

Prepare the Shrimp

Boil the jumbo shrimp in salted water for 2-3 minutes until they turn pink. Drain and chill them in ice water.

Serve

Arrange the chilled shrimp on a platter with cocktail sauce and spicy mustard sauce on the side for dipping.