Instructions

1. Preheat oven to 375°F.
2. Heat olive oil in a large pan. Cook onion for 5–7 minutes until softened, then add garlic and cook for another 30–60 seconds.
3. Add chicken sausage and cook until browned, breaking it apart as it cooks. Stir in the red bell pepper and cook for 3–4 minutes.
4. Add crushed tomatoes, tomato sauce, tomato paste, and chopped Roma tomatoes. Season with Italian seasoning, crushed red pepper, and black pepper. Simmer for 20–30 minutes until slightly thickened.
5. Prepare vegetables: lightly salt zucchini slices and let sit for 10 minutes, then pat dry. Wilt spinach in a pan and squeeze out excess moisture.
6. Mix ricotta, egg, Parmesan, lemon zest (or juice), salt, and pepper until smooth.
7. Assemble in a 9×13 dish: spread a thin layer of sauce, then layer noodles, ricotta mixture, vegetables, sauce, and mozzarella. Repeat for 2–3 layers.
8. Finish with sauce, mozzarella, and a generous sprinkle of Parmesan.
9. Bake covered for 30 minutes, then uncover and bake an additional 10–15 minutes until bubbly and lightly golden. Broil briefly if desired.
10. Let rest for 15–20 minutes before slicing and serving.