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- 2 large onions, thinly sliced - 2 tablespoons olive oil - 1 tablespoon butter - 1 teaspoon sugar - Salt and pepper to taste - 4 slices of crusty bread (like sourdough or French bread) - 8 slices of Gruyère cheese (or a mix of Gruyère and Swiss) - 1 tablespoon fresh thyme leaves (or 1 teaspoon dried thyme) - 1/2 cup beef or vegetable broth - Optional: 1 tablespoon balsamic vinegar for added depth

French Onion Grilled Cheese Sandwich

Elevate your lunch with this irresistible French Onion Grilled Cheese Sandwich! Enjoy the perfect blend of gooey Gruyère cheese and sweet caramelized onions, all tucked between slices of crusty bread. This delightful recipe walks you through each step, from caramelizing onions to achieving that golden, crispy finish. Dive into this comforting dish today and discover tips for flavor enhancements. Click through for the full recipe and impress everyone with your culinary skills!
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Ingredients
  

2 large onions, thinly sliced

2 tablespoons olive oil

1 tablespoon butter

1 teaspoon sugar

Salt and pepper to taste

4 slices of crusty bread (like sourdough or French bread)

8 slices of Gruyère cheese (or a mix of Gruyère and Swiss)

1 tablespoon fresh thyme leaves (or 1 teaspoon dried thyme)

1/2 cup beef or vegetable broth

Optional: 1 tablespoon balsamic vinegar for added depth

Instructions
 

Caramelize the Onions: In a large skillet, heat the olive oil and butter over medium heat. Add the sliced onions and stir to coat. Sprinkle with sugar, salt, and pepper. Cook, stirring occasionally, for about 20-25 minutes until the onions are golden brown and caramelized. If needed, add the broth and balsamic vinegar in the last 10 minutes to deepen the flavor, allowing it to cook off and create a sticky texture. Add thyme leaves during the last minute of cooking.

    Prepare the Sandwiches: While the onions are caramelizing, preheat a separate skillet over medium heat. Assemble the grilled cheese sandwiches by placing 2 slices of bread on a clean surface. Layer 2 slices of Gruyère cheese on each, followed by a generous scoop of the caramelized onions, then cover with the remaining cheese and top with the final slices of bread.

      Grill the Sandwiches: Once the skillet is hot, add a bit of olive oil or butter. Carefully place the assembled sandwiches in the skillet. Grill for about 4-5 minutes on one side, or until golden brown and crispy. Carefully flip the sandwiches and grill the other side for another 4-5 minutes, pressing lightly with a spatula to ensure even toasting.

        Serve: Once both sides are golden and the cheese is melted, remove the sandwiches from the skillet. Let them cool for a minute before slicing them in half. Optionally, garnish with more fresh thyme.

          - Prep Time: 15 minutes | Total Time: 45 minutes | Servings: 2 Sandwiches

            - Presentation Tips: Serve the sandwiches with a side of homemade soup or a simple side salad, and garnish with a sprinkle of fresh thyme or a drizzle of balsamic reduction for a pop of color. Enjoy hot!