French Onion Soup au Gratin Recipe
Prep Time:
15 minutes
Cook Time:
32 minutes
Servings:
12 Servings
Ingredients
  • 3 pound red onions, sliced 1/4-inch thick
  • 3 pound yellow onions, sliced 1/4-inch thick
  • 1/2 tablespoon minced garlic
  • 1 1/2 cups cooking sherry
  • 3 quarts water
  • 4 ounce beef bouillon base
  • 4 ounce veal demi-glace base
  • 3/4 teaspoon ground white pepper
  • 1 1/2 tablespoons granulated onion
  • 3 cup croutons
  • 24 ounce grated gruyere cheese
  • 24 ounce grated mozzarella cheese
Directions
  1. In a large stock pot over medium-high heat, melt 4 ounces (1 stick) unsalted butter. Add 3 pounds sliced red onions and 3 pounds sliced yellow onions. Sauté until caramelized. Add 1/2 tablespoon minced garlic and cook for an additional 5 minutes, stirring frequently.
  2. Add 1 1/2 cups cooking sherry to deglaze, reduce heat and simmer until almost dry.
  3. Add 3 quarts water, 4 ounces beef bouillon base, 4 ounces veal demi-glace base, 3/4 teaspoon ground white pepper and 1 1/2 tablespoons granulated onion. Simmer for 30 minutes, stirring frequently.
  4. To serve, preheat broiler to high. Using an ovenproof crock or bowl, ladle soup into bowl. Top each serving with 1/4 cup croutons. This keeps the cheese from sinking.
  5. Sprinkle each serving with 2 ounces Gruyere and 2 ounces mozzarella cheese. Place under broiler until golden brown and bubbly, serve immediately.