Go Back

French Onion Grilled Cheese Sandwich Recipe

This gourmet sandwich takes the humble grilled cheese to new heights. It uses sophisticated techniques and mouthwatering ingredients. Home cooks and food enthusiasts will love this elevated comfort food that blends French cuisine with American sandwich traditions.
Print Recipe Pin Recipe
Ingredients Equipment Method

Ingredients
  

  • For the Caramelized Onions:
  • 2 large onions thinly sliced
  • 2 tbsp butter
  • 1 tbsp olive oil
  • ½ tsp salt
  • ½ tsp black pepper
  • ½ tsp sugar optional, for extra sweetness
  • ¼ cup beef broth or white wine for depth
  • 1 tsp Worcestershire sauce
  • ½ tsp dried thyme or 1 tsp fresh thyme
  • For the Sandwich:
  • 4 slices sourdough or French bread
  • 2 tbsp butter softened
  • ½ tsp garlic powder
  • ½ tsp dried parsley optional
  • 1 cup shredded Gruyère cheese or Swiss
  • ½ cup shredded mozzarella cheese for extra melt

Equipment

  • Large skillet or frying pan
  • Wooden spoon or spatula
  • Cutting board & knife
  • Cheese grater (if using block cheese)
  • Small bowl (for butter mixture)

Method
 

  1. Caramelize the Onions:
  2. Heat butter and olive oil in a skillet over medium-low heat.
  3. Add sliced onions, salt, pepper, and sugar. Cook, stirring occasionally, for 20-25 minutes until golden brown.
  4. Stir in beef broth, Worcestershire sauce, and thyme. Simmer for 2-3 minutes until onions are jammy. Set aside.
  5. Prepare the Butter Spread:
  6. In a small bowl, mix softened butter with garlic powder and parsley.
  7. Assemble the Sandwich:
  8. Spread the butter mixture on one side of each bread slice.
  9. On the unbuttered side, layer Gruyère, caramelized onions, and mozzarella.
  10. Top with another slice of bread, buttered side facing out.
  11. Grill the Sandwich:
  12. Heat a skillet over medium heat.
  13. Cook sandwiches for 3-4 minutes per side until golden brown and crispy, and the cheese is fully melted.
  14. Serve & Enjoy:
  15. Slice in half and serve warm. Pair with tomato soup or a side salad for a complete meal!
  16. Preparing the Caramelized Onions