French Onion–Potato Soup

French Onion-Potato Soup

You don’t have to choose between your two favorite soups with this hearty French Onion-Potato Soup.

French Onion–Potato Soup
Makes 8 servings
  • 1 tablespoon olive oil
  • 2 tablespoons unsalted butter
  • 8 cups thinly sliced yellow onion
  • 1 teaspoon kosher salt
  • 1 teaspoon sugar
  • 6 cups beef broth
  • 1 cup dry sherry
  • 2 tablespoons Worcestershire sauce
  • 4 sprigs fresh thyme
  • 2 bay leaves
  • 1 pound baby Yukon gold potatoes, cut into 1-inch pieces
  • 1 teaspoon fresh thyme leaves
  • 1 cup grated Gruyère cheese
  • ½ cup grated Parmesan cheese
  • 16 thick slices French bread
  • Garnish: fresh thyme
  1. In a large Dutch oven, heat oil and butter over medium-low heat. Add onion; cook, stirring occasionally, until softened, 15 to 20 minutes. Stir in salt and sugar; cook, stirring frequently, until onions are caramelized, 45 minutes to 1 hour. (If onions start to stick to the pan or burn, add 1 tablespoon beef broth to deglaze.)
  2. Stir in beef broth, sherry, Worcestershire, thyme sprigs, and bay leaves. Increase heat and bring to a boil. Add potatoes; reduce heat and simmer, stirring occasionally, until potatoes are tender, about 20 minutes. Remove thyme sprigs and bay leaves; stir in thyme leaves.
  3. Preheat oven to 400°. Arrange 8 (1-cup) heatproof dishes or ramekins on a rimmed baking sheet.
  4. In a small bowl, stir together Gruyère and Parmesan. Ladle soup into prepared dishes. Top each portion with 2 bread slices. Sprinkle with cheese mixture.
  5. Bake until cheese is melted and golden brown, 3 to 5 minutes. Garnish with thyme, if desired.
KITCHEN TIP-For added depth of flavor, add 2 tablespoons brandy at the end of step 1.