Florentine Lasagna

Name: Florentine Lasagna
Ingredients: 12 ounces italian sausage; 1/2 cup onion; 2 cloves garlic; 8 ounce tomato sauce; 7 1/2 ounce tomatoes; 1 teaspoon dried oregano; 1 teaspoon dried basil; 6 lasagna noodles; 1 egg; 15 ounce ricotta cheese; 1/3 cup parmesan cheese; 1/4 teaspoon pepper; 10 ounce frozen spinach; 8 ounce mozzarella; 1 teaspoon extra virgin olive oil