A comforting and classic French Onion Soup recipe that features deeply caramelized onions, rich beef broth, and gooey melted Gruyère cheese. Perfect for a cozy night in or as a starter for a special meal.
Caramelize Onions: In a large pot, melt butter and olive oil over medium heat. Add onions, sugar, salt, and pepper. Cook for 25–30 minutes until golden and caramelized. Add garlic and cook for another minute.
Deglaze and Simmer: Pour in white wine (if using) to deglaze. Stir in beef broth, Worcestershire sauce, thyme, and bay leaf. Simmer, covered, for 20–25 minutes.
Broil and Serve: Preheat broiler. Ladle soup into bowls, top with baguette and Gruyère. Broil for 2–3 minutes until cheese is melted. Serve hot.
Notes
For a vegetarian version, use vegetable broth and skip Worcestershire sauce.
Swiss or provolone cheese can be used if Gruyère is not available.