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Frittatas are a culinary treasure known for their adaptability and rich flavors. Originating from Italy, this dish marries eggs with a variety of ingredients, making it an ideal choice for breakfast, brunch, or even dinner. Among the many frittata variations, the Caramelized Onion and Mushroom Frittata stands out with its deep, savory flavors and satisfying texture. This dish not only showcases the natural sweetness of caramelized onions but also highlights the earthy goodness of mushrooms, creating a harmonious blend that appeals to both the palate and the eye.

Caramelized Onion and Mushroom Frittata

Discover the deliciousness of the Caramelized Onion and Mushroom Frittata, the perfect dish for any meal of the day! This versatile Italian classic combines protein-packed eggs with the sweetness of caramelized onions and earthy mushrooms, creating a satisfying meal that's also nutritious. Easy to customize with your favorite veggies or cheese, it's great for meal prep and can be enjoyed warm or chilled. Try this comforting recipe that’s sure to impress everyone!
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Ingredients
  

6 large eggs

1 cup whole milk

2 tablespoons extra virgin olive oil

1 large onion, thinly sliced

8 ounces cremini or button mushrooms, sliced

1 teaspoon fresh thyme (or ½ teaspoon dried thyme)

Salt and freshly ground black pepper, to taste

½ cup grated mozzarella cheese (optional, for added richness)

Fresh parsley, chopped (for garnish)

Instructions
 

Preheat the Oven: Start by preheating your oven to 375°F (190°C) to prepare for baking the frittata.

    Caramelize the Onions: In a large, oven-safe skillet, heat the olive oil over medium heat. Add the thinly sliced onions to the skillet and cook them slowly, stirring occasionally. Allow them to caramelize for about 15 minutes, or until they are golden brown and have a sweet aroma. If the onions start to stick to the skillet, add a splash of water or a bit more olive oil to keep them from burning.

      Add the Mushrooms: Once your onions are beautifully caramelized, incorporate the sliced mushrooms into the skillet. Sauté the mushrooms with the onions for 5-7 minutes, stirring occasionally, until they are tender and most of their moisture has evaporated.

        Whisk the Egg Mixture: In a large mixing bowl, combine the eggs, whole milk, fresh thyme (or dried thyme), salt, and pepper. Whisk them together vigorously until the mixture is well blended.

          Combine Ingredients: Carefully pour the egg mixture over the caramelized onions and mushrooms in the skillet. Gently stir to ensure that the vegetables are evenly distributed throughout the egg mixture. If you are adding mozzarella cheese, sprinkle it over the top for a deliciously cheesy finish.

            Initial Cooking on the Stovetop: Place the skillet back on the stovetop over medium heat. Cook for about 5 minutes, allowing the edges of the frittata to start setting while the center remains slightly runny.

              Bake the Frittata: Transfer the skillet to the preheated oven. Bake for 15-20 minutes, or until the frittata has puffed up, turned golden brown on top, and a toothpick inserted into the center comes out clean.

                Serve: Once baked, remove the frittata from the oven and let it cool for a few minutes. Before serving, garnish with freshly chopped parsley. Slice into wedges and enjoy warm, or allow to come to room temperature for a delightful brunch option.

                  Prep Time, Total Time, Servings: 15 minutes | 40 minutes | Serves 4