french-onion-soup-casserole

Winter Best Food

French Onion Soup Casserole

This hearty, homey take on French onion soup celebrates Georgia-grown Vidalia onions.

Ingredients

  • 1/4 cup unsalted butter
  • 5 medium Vidalia onions, thinly sliced (about 3 lb.)
  • 2 tsp. kosher salt
  • 1/2 tsp. black pepper
  • 3 thyme sprigs
  • 2 flat-leaf parsley sprigs
  • 2 bay leaves
  • 1 (16-oz.) baguette, thinly sliced
  • 1/3 cup all-purpose flour
  • 3 cups reduced-sodium beef broth
  • 1/2 cup sherry
  • 8 oz. Gruyère cheese, shredded (about 2 cups)
  • 1 tsp. fresh thyme leaves

Directions

  1. Cook onions:

    Melt butter in a Dutch oven over medium-low; add onions, salt, pepper, thyme and parsley sprigs, and bay leaves; cook, stirring often, until onions are golden brown, about 1 hour.

  2. Toast baguette slices:

    Meanwhile, preheat oven to 350°F. Arrange baguette slices in a single layer on a baking sheet. Bake in preheated oven until lightly toasted, 12 minutes. Set aside.

  3. Make sauce:

    Remove and discard thyme and parsley sprigs and bay leaves from onion mixture. Add flour, and cook, stirring constantly, 2 minutes. Add broth and sherry; bring to a boil over high. Boil, stirring constantly, until slightly thickened, 2 to 3 minutes.

  4. Assemble casserole:

    Layer half of the toasted baguette slices in a 13- x 9-inch baking dish. Spoon onion mixture evenly over bread. Top evenly with remaining baguette slices. Sprinkle with cheese; cover with aluminum foil.

  5. Bake casserole:

    Bake in preheated oven 30 minutes. Increase heat to broil. Remove foil; broil until cheese is bubbly, about 3 minutes. Sprinkle with thyme leaves.