To make the sauce: Heat oven to 350F. In a pot, heat oil and sauté garlic, onions and hot pepper flakes until golden.
Stir in tomato paste. Rinse can with the water and add to pot. Simmer 30 minutes. Add all the remaining ingredients.
Simmer at least 1 ½ to 2 hours. If you have more time, let it simmer even a little longer.
To make the filling: Combine ricotta, pepper, parsley and eggs in medium bowl. Mix thoroughly. Reserve cheeses.
To assemble the casserole: Cook rigatoni according to package directions but reduce cooking time by two minutes. Do not overcook.
Spread sauce over the bottom of a 9x13x2 inch baking dish. Top with a layer of pasta. Top pasta with a little more sauce. Then several spoons full of ricotta mixture. Spoon together with the back of a large spoon.
Top with a sprinkling of mozzarella cheese. Top with a layer of pasta and repeat process, ending with parmesan this time. Then repeat, ending with mozzarella, etc. Finish with a layer of pasta.
Bake for 30-35 minutes or for about 15 minutes after it begins to bubble around edges. Ricotta will rise to top, it should be slightly set.
Allow to stand 10-15 minutes before serving. Serves six to eight.
