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- 4 slices of sourdough bread - 2 cups yellow onions, thinly sliced - 2 tablespoons unsalted butter - 1 tablespoon olive oil - 1 teaspoon sugar - 1 teaspoon salt - 1 teaspoon fresh thyme leaves (or ½ teaspoon dried thyme) - 1 cup shredded Gruyère cheese - ½ cup shredded mozzarella cheese - ¼ cup beef or vegetable broth - Freshly ground black pepper, to taste

French Onion Grilled Cheese

Discover the ultimate comfort food with this French Onion Grilled Cheese recipe! This delicious dish features caramelized onions, gooey cheese, and crispy sourdough bread that come together for an unforgettable meal. Perfect for any day, you’ll love the rich flavors and simple preparation. Want to impress your family and friends? Check out the full recipe and elevate your grilled cheese game today!
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Ingredients
  

4 slices of sourdough bread

2 cups yellow onions, thinly sliced

2 tablespoons unsalted butter

1 tablespoon olive oil

1 teaspoon sugar

1 teaspoon salt

1 teaspoon fresh thyme leaves (or ½ teaspoon dried thyme)

1 cup shredded Gruyère cheese

½ cup shredded mozzarella cheese

¼ cup beef or vegetable broth

Freshly ground black pepper, to taste

Instructions
 

In a large skillet, heat the butter and olive oil over medium heat.

    Add the sliced onions, salt, and sugar to the skillet. Cook, stirring occasionally, until the onions are soft and caramelized—about 15-20 minutes.

      Once the onions are golden brown, add the thyme and broth. Cook for an additional 5 minutes, allowing the liquid to reduce slightly. Remove from heat and set aside.

        In another skillet, heat over medium heat. Place two slices of sourdough in the skillet.

          Layer half of the caramelized onions onto each slice in the skillet, then sprinkle with Gruyère and mozzarella cheeses. Top with the remaining caramelized onions.

            Finally, place another slice of sourdough on top to form a sandwich.

              Cook for 3-4 minutes, then carefully flip the sandwich over and cook for an additional 3-4 minutes, or until both sides are golden brown and the cheese is melted.

                Remove from the pan, slice in half, and serve warm, with any remaining caramelized onions on the side if desired.

                  Prep Time: 15 minutes | Total Time: 40 minutes | Servings: 2

                    - Presentation Tips: Serve the grilled cheese on a rustic wooden board, accompanied by a small bowl of creamy tomato soup for dipping and garnish with a sprig of thyme on top.