Go Back
comforting onion soup recipe

Caramelized French Onion Soup

This soul-warming Caramelized French Onion Soup features sweet onions slowly transformed into golden perfection, simmered in rich beef broth with a hint of brandy. Topped with crusty bread and a trio of melted cheeses, it's the ultimate comfort food for cold days.
Print Recipe Pin Recipe
Prep Time 20 minutes
Cook Time 1 hour 30 minutes
Total Time 1 hour 50 minutes
Servings: 8 people
Course: Soup
Cuisine: French
Calories: 485
Ingredients Equipment Method Notes

Ingredients
  

  • 1/2 teaspoon dried thyme
  • 1 teaspoon sugar helps with caramelization
  • 3 tablespoons all-purpose flour
  • 1 1/2 cups dry white wine
  • 4 whole garlic cloves
  • 4 tablespoons butter
  • 2 tablespoons olive oil
  • 1/4 cup brandy
  • 6 cups yellow onions thinly sliced
  • 3 quarts beef stock
  • 1 tablespoon Dijon mustard
  • Salt and black pepper to taste
For the Cheesy Croutons
  • 8 slices French bread thick
  • 4 tablespoons butter softened
  • 4 tablespoons olive oil
  • 3 cloves garlic minced
  • 8 ounces Gruyère cheese shredded
  • 8 ounces mozzarella cheese shredded
  • 4 ounces Parmesan cheese freshly grated

Equipment

  • Large heavy pot
  • Oven-proof soup bowls
  • Broiler

Method
 

  1. In a large, heavy pot over medium heat, melt 4 tablespoons of butter with 2 tablespoons of olive oil.
  2. Add the thinly sliced yellow onions and increase heat to high. Stir frequently for about 15 minutes until the onions become golden and soft.
  3. Reduce heat to medium, then add the whole garlic cloves and sugar. Continue cooking for another 20 minutes, stirring occasionally.
  4. Using a fork, mash the softened garlic cloves directly in the pot.
  5. Carefully add the brandy (standing back to avoid steam), and stir to deglaze the pot, scraping up any browned bits from the bottom.
  6. Stir in the Dijon mustard, dried thyme, and flour. Cook for 3 minutes, stirring constantly to remove the raw flour taste.
  7. Gradually pour in the beef stock and white wine. Season with salt and pepper to taste.
  8. Allow the soup to simmer uncovered for 30-45 minutes, letting the flavors meld together.
  9. While the soup simmers, preheat your oven to 350°F (175°C).
  10. For the croutons, mix the softened butter, olive oil, and minced garlic in a small bowl. Spread this mixture on both sides of the French bread slices.
  11. Place the bread slices on a baking sheet and toast in the oven for 12-15 minutes until golden and crisp. Remove and set aside.
  12. Preheat your broiler. In a bowl, combine the shredded Gruyère, mozzarella, and Parmesan cheeses.
  13. Ladle the hot soup into oven-proof bowls. Float a toasted crouton on top of each bowl of soup.
  14. Generously cover each crouton with the cheese mixture, allowing some to spill over the edges of the bowl.
  15. Place the bowls under the broiler for about 4 minutes, watching carefully until the cheese becomes bubbly and browned.
  16. Serve immediately, cautioning guests about the hot temperature.

Notes

The key to exceptional French onion soup is patience during the onion caramelization process—don't rush this step as it builds the foundation of flavor. For the best cheese pull, use freshly grated cheese rather than pre-shredded varieties, as they melt more smoothly.
This soup can be made a day ahead (without the bread and cheese topping) and refrigerated, which actually improves the flavor. Simply reheat before adding the croutons and cheese.
Leftover soup can be stored in the refrigerator for up to 4 days. For freezing, store only the soup base without the bread and cheese for up to 3 months.