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To create the perfect caramelized onion and Gruyère stuffed mushrooms, it’s essential to understand the key components that contribute to the dish’s rich flavor profile. Using fresh, high-quality ingredients not only enhances the taste but also ensures that you maximize the nutritional value of your meal.

Caramelized Onion & Gruyère Stuffed Mushrooms – Elegant & Flavorful!

Discover the irresistible blend of flavors in Caramelized Onion & Gruyère Stuffed Mushrooms, an appetizer that impresses at any gathering. The sweet, rich caramelized onions paired with nutty Gruyère cheese create a delightfully sophisticated dish. This guide walks you through selecting fresh ingredients, preparing, and baking your mushrooms to perfection. Customize your stuffing with herbs, veggies, or meats for a unique twist. Perfect for dinner parties or cozy family meals!
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Ingredients
  

1 pound large cremini or portobello mushrooms (stems removed)

2 tablespoons olive oil

2 medium onions, thinly sliced

3 cloves garlic, minced

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

Salt and pepper to taste

1 cup Gruyère cheese, grated

½ cup breadcrumbs (preferably panko for extra crunch)

2 tablespoons fresh parsley, chopped (for garnish)

1 tablespoon balsamic vinegar

Instructions
 

Preheat the Oven: Preheat your oven to 375°F (190°C).

    Sauté the Onions: In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add the sliced onions, and cook, stirring occasionally, for about 15-20 minutes until they are golden brown and caramelized. If they start to stick, you can add a splash of water to the pan. Add the minced garlic and thyme, and cook for another 1-2 minutes until fragrant. Season with salt and pepper, then stir in the balsamic vinegar. Remove from heat and let it cool slightly.

      Prepare the Mushroom Caps: In a baking dish, arrange the mushroom caps, gill side up. Brush the tops lightly with olive oil and season with salt and pepper.

        Make the Filling: In a mixing bowl, combine the caramelized onion mixture, grated Gruyère cheese, and breadcrumbs. Stir until well combined. Adjust seasoning if necessary.

          Stuff the Mushrooms: Generously fill each mushroom cap with the Gruyère and caramelized onion mixture, pressing down slightly to pack it in.

            Bake: Bake the stuffed mushrooms in the oven for about 20-25 minutes, or until the tops are golden brown and the mushrooms are tender.

              Garnish and Serve: Remove from the oven and let cool slightly. Garnish with freshly chopped parsley before serving.

                Prep Time, Total Time, Servings: 15 minutes | 40 minutes | Serves 4-6 as an appetizer