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Frittatas are a beloved dish celebrated for their versatility, serving as a delicious option for breakfast, lunch, or dinner. This Caramelized Onion and Mushroom Frittata is a prime example of how simple ingredients can come together to create a meal that is both savory and satisfying. The rich flavors of sweet caramelized onions combined with the earthiness of mushrooms transform this dish into a gourmet experience right from your kitchen.

Caramelized Onion and Mushroom Frittata

Discover the delightful flavors of this Caramelized Onion and Mushroom Frittata, perfect for any meal of the day. With its rich combination of sweet caramelized onions, earthy mushrooms, and fluffy eggs, this versatile dish is not only delicious but also packed with nutrients. Follow our step-by-step guide to create this gourmet experience at home. Learn about the key ingredients, cooking techniques, and tips to serve it beautifully. Enjoy a nutritious meal that's sure to impress!
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Ingredients
  

6 large eggs

1 cup milk

2 tablespoons olive oil

1 large onion, thinly sliced

8 ounces cremini or button mushrooms, sliced

1 teaspoon fresh thyme (or 1/2 teaspoon dried thyme)

Salt and pepper, to taste

1/2 cup grated mozzarella cheese (optional)

Fresh parsley, chopped (for garnish)

Instructions
 

Preheat the Oven: Set your oven temperature to 375°F (190°C) to ensure it's ready 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 and cook slowly, stirring occasionally, for approximately 15 minutes. The onions should turn a deep golden brown and become caramelized. If they begin to stick to the pan, add a splash of water or a bit more olive oil to maintain moisture.

      Add the Mushrooms: Once the onions are beautifully caramelized, incorporate the sliced mushrooms into the skillet. Sauté them for about 5-7 minutes until they soften and any liquid released has evaporated, allowing them to blend harmoniously with the onions.

        Mix the Eggs and Milk: In a large mixing bowl, whisk together the eggs and milk until fully combined. Add in the thyme, along with a generous seasoning of salt and pepper.

          Combine Ingredients: Carefully pour the egg mixture over the caramelized onions and mushrooms in the skillet. Gently stir to ensure even distribution of the vegetables. If you're using mozzarella cheese, sprinkle it evenly over the top.

            Cook on the Stovetop: Place the skillet back on the stove over medium heat. Allow it to cook for about 5 minutes, during which time the edges will begin to set while the center remains slightly runny.

              Bake to Finish: Transfer your skillet to the preheated oven and bake for 15-20 minutes. The frittata is ready when it is puffed, golden brown, and a toothpick inserted in the center comes out clean.

                Serve: Once baked, remove the skillet from the oven and let it cool for a few minutes. Garnish with freshly chopped parsley, then slice into wedges and serve warm or at room temperature.

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