01 -
Preheat oven to 375°F (190°C). Cook lasagna noodles in boiling salted water according to package instructions until al dente, approximately 8 to 10 minutes. Drain and lay flat to prevent sticking.
02 -
In a large skillet, heat olive oil over medium heat. Add chopped onion and minced garlic; sauté for 3 to 4 minutes until softened. Add diced zucchini, red bell pepper, yellow bell pepper, and mushrooms. Cook for 5 to 7 minutes until vegetables are tender.
03 -
Stir fresh spinach into the skillet and cook until wilted. Add marinara sauce, dried basil, and dried oregano. Simmer the mixture over low heat for 5 minutes.
04 -
In a medium mixing bowl, combine ricotta cheese, beaten egg, salt, and black pepper. Mix until smooth and homogeneous.
05 -
In a 9x13-inch baking dish, spread a layer of the prepared vegetable sauce, followed by a layer of noodles. Spoon half of the ricotta mixture over the noodles, top with a portion of the vegetables, and sprinkle with 1 cup of mozzarella cheese. Repeat the layering process with the remaining ingredients.
06 -
Place the final layer of noodles, spread remaining marinara sauce evenly, sprinkle with the rest of the mozzarella cheese and the grated parmesan cheese.
07 -
Cover the baking dish tightly with aluminum foil and bake for 25 minutes. Remove the foil and bake for an additional 15 minutes, or until bubbling and golden brown.
08 -
Allow lasagna to rest for 10 minutes before slicing and serving for easier portioning.