Creating Three-Cheese Lasagna with Roasted Red Peppers and Mushrooms is straightforward. Follow these steps for a delicious outcome:

1. Preheat the Oven: Set your oven to 375°F (190°C) to preheat while preparing the lasagna.

2. Cook the Noodles: In a large pot, bring salted water to a boil and cook the lasagna noodles according to package instructions. Drain and set aside.

3. Sauté the Vegetables: In a skillet, heat olive oil over medium heat. Add minced garlic and sliced mushrooms, cooking until the mushrooms are tender. Stir in roasted red peppers, oregano, basil, salt, and pepper. Cook for an additional 2-3 minutes for flavors to meld.

4. Mix the Cheese Filling: In a medium bowl, combine ricotta cheese, 1 cup of mozzarella cheese, Parmesan cheese, and the egg. Mix until smooth and well combined.

5. Assemble the Lasagna:
– Layer 1: Spread a thin layer of marinara sauce on the bottom of a 9×13-inch baking dish.
– Layer 2: Place three lasagna noodles over the sauce.
– Layer 3: Spread half of the cheese mixture over the noodles.
– Layer 4: Top with half of the sautéed mushroom and roasted pepper mixture.
– Layer 5: Add another layer of marinara sauce.
– Repeat the layers: noodles, cheese mixture, mushroom-pepper mix, and marinara sauce again.
– Finish with a final layer of noodles topped with remaining marinara sauce and the rest of the mozzarella cheese.

6. Bake the Lasagna: Cover the baking dish with aluminum foil and bake for 25 minutes. Remove foil and bake for an additional 20 minutes, or until the cheese is golden and bubbly.

7. Cool Slightly: Remove the lasagna from the oven and let it cool for about 15 minutes. This allows the layers to set.

8. Serve: Garnish with fresh basil before slicing and serving.

These steps ensure that your Three-Cheese Lasagna is not only delicious but also beautifully layered and satisfying.