Preheat oven to 400°F (205°C). Line a large baking sheet with parchment paper.

Toss mushrooms, bell peppers, zucchini, and carrots with olive oil, salt, and pepper. Roast for 25 minutes, then set aside.

Heat olive oil in a large pot over medium-high heat. Sauté onion until translucent.

Add garlic, Italian seasoning, and oregano. Cook 1–2 minutes.

Stir in marinara sauce, bay leaf, salt, and pepper. Reduce heat, cover, and simmer for 12 minutes. Remove bay leaf and set aside.

In another pan, heat olive oil and sauté spinach until wilted, 3–5 minutes.

In a bowl, combine spinach, egg white, ricotta, lemon juice, parsley, basil, and parmesan. Mix well.

Cook lasagna noodles according to package instructions. Drain and cool.

Spread 1 cup marinara sauce in an 8×8-inch baking dish.

Layer 4 noodles, ½ cup ricotta mixture, 1¼ cups mozzarella, and ⅓ of roasted vegetables.

Repeat for a second layer.

For the final layer, add noodles, ricotta, vegetables, and remaining marinara (no mozzarella yet).

Bake uncovered for 25 minutes.

Remove from oven, top with remaining mozzarella, cover, and bake 20 more minutes.

Rest 15 minutes before topping with parmesan and fresh basil.