1. Slice zucchini into 1/8 inch slices, lengthwise and place on a lightly greased baking sheet. Bake at 425 degrees for 12-14 minutes. Place on paper towels to remove moisture.
2. Heat 2 TB olive oil, add 1 medium chopped onion, and 4 cloves garlic, minced. Stir 1minute.
3. Add 2 TB tomato paste, 28 oz crushed tomatoes, and salt and pepper to taste. Simmer 30 minutes. Add 2 cups spinach and cook until wilted. Remove from heat.
4. In a large bowl, mix 15 oz ricotta cheese, 1/2 cup Parmesan cheese, 8 oz mozzarella cheese, 8 oz pepper jack cheese, 1 large egg, 1 TB dried basil, 1 tp Italian seasoning, 1/4 tp red pepper flakes, 1/2 tp salt and 1/4 tp pepper to taste. Stir ( it’ll be thick).
5. Spread 1/2 cup of cheese mixture, 1 layer of zucchini, 1/2 remaining cheese, top with spinach, zucchini, rest of cheese, spinach, zucchini, 1 cup marinara sauce, and 1 cup mozzarella cheese.
6. Bake at375 degrees, covered with foil, for 30 minutes..uncover and bake an additional 20-30 minutes. Let sit 15 minutes, slice and garnish with parsley.