French Onion Grilled Cheese

Total Time Prep: 20 min. Cook: 30 min.
Yield 4 servings
Test Kitchen Approved
This French onion grilled cheese recipe is the dressed-up, grown-up version of the beloved childhood sandwich.

Ingredients

  • 5 tablespoons butter, softened, divided
  • 1 tablespoon olive oil
  • 2 medium onions, thinly sliced
  • 1/2 teaspoon dried thyme
  • 1/2 teaspoon dried rosemary, crushed
  • 1 bay leaf
  • 1 teaspoon packed brown sugar
  • 1/2 teaspoon pepper
  • 3 tablespoons grated Parmesan cheese
  • 1/4 cup water
  • 1 ounce au jus gravy mix
  • 8 slices sourdough bread
  • 8 slices Swiss cheese
  • 1 cup shredded Gruyere cheese

Directions

  1. In a large skillet, heat 1 tablespoon butter and olive oil over medium heat. Add onion, thyme, rosemary, bay leaf, brown sugar and pepper. Cover; cook over medium-low heat for 15-20 minutes, stirring occasionally, until onions are soft and lightly browned.
  2. Meanwhile, in a small bowl, combine Parmesan cheese and remaining 4 tablespoons softened butter; set aside.
  3. Remove the lid from the skillet; increase heat to medium. Add water and aus jus mix; simmer until reduced, 2-3 minutes. Remove from heat; discard bay leaf.
  4. Preheat a large nonstick skillet or griddle over medium heat.
  5. Top each slice of bread with two slices Swiss cheese and 1/4 of the onion mixture. Sprinkle each with 1/4 cup Gruyere; top with another slice of bread. Spread both sides of each sandwich with Parmesan butter.
  6. Place sandwiches on the preheated griddle. Cook until golden brown and cheese is melted, 3-4 minutes per side. Remove to a cutting board; cut each sandwich in half. Serve immediately.

Nutrition Facts

1 serving: 796 calories, 46g fat (25g saturated fat), 124mg cholesterol, 2000mg sodium, 62g carbohydrate (8g sugars, 3g fiber), 35g protein.

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