In a medium stockpot combine the diced tomatoes, tomato sauce, chopped onion, Italian seasoning, salt and water. Stir in the minced garlic in quantity desired. Allow mixture to simmer for 2 hours. If sauce seems dry add additional water. In large pot of boiling salted water cook the ravioli until done and drain. In a 9x13 inch pan layer sauce and cooked ravioli. Top with grated Parmesan cheese and grated mozzarella cheese. In a preheated 400 degrees oven bake for 30 minutes, or until light golden brown; let cool 15 minutes before serving.
Ready in 1 hour