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For the French Onion Grilled Cheese, you will need these tasty ingredients. Each one plays a role in making this dish special.

French Onion Grilled Cheese

Indulge in the ultimate comfort food with this mouthwatering French Onion Grilled Cheese! This delicious sandwich features rich, caramelized onions paired with gooey melted cheese, all tucked between crispy sourdough. Follow our easy step-by-step guide to create a warm, cheesy masterpiece that will become your new favorite meal. Click through for the full recipe and elevate your grilled cheese game today!
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Ingredients
  

2 large yellow onions, thinly sliced

4 tablespoons unsalted butter

1 teaspoon sugar

1 teaspoon salt

1 teaspoon black pepper

1 teaspoon fresh thyme leaves (or ½ teaspoon dried)

8 slices of sourdough bread

1 cup grated Gruyère cheese

1 cup grated sharp cheddar cheese

2 tablespoons Dijon mustard

Olive oil for grilling

Instructions
 

In a large skillet, melt the butter over medium heat. Add the sliced onions and season with salt. Cook for about 10 minutes, stirring occasionally.

    Add the sugar and continue to cook for another 15-20 minutes, stirring frequently until the onions are caramelized and golden brown. Add black pepper and thyme during the last few minutes of cooking.

      Remove the skillet from heat and set the caramelized onions aside.

        Preheat a griddle or large skillet over medium heat.

          Assemble the sandwiches: Spread Dijon mustard on one side of each slice of sourdough bread. On the unspread side, layer half of the cheese mix (Gruyère and cheddar), followed by a generous amount of the caramelized onions, and then the remaining cheese on top. Close the sandwich with another slice of bread, mustard side down.

            Lightly brush the outside of each sandwich with olive oil.

              Grill the sandwiches on the preheated griddle for about 3-4 minutes on each side until golden brown and the cheese is melted. If necessary, press down lightly with a spatula to ensure even grilling.

                Remove from heat, cut in half, and let cool slightly before serving.

                  Prep Time: 15 minutes | Total Time: 50 minutes | Servings: 4

                    - Presentation Tips: Serve the grilled cheese sandwiches on a rustic wooden board or cutting board, with a side of homemade tomato soup or a small salad for a complete meal. Garnish with fresh thyme sprigs for an aromatic touch. Enjoy your delicious French Onion Grilled Cheese Delight!