Preheat the oven to 400 degrees F. Grease a 9x13 or casserole pan with cooking spray. Fill a large pasta pot more than halfway full with hot water. Add some salt and put the pot on the stove, covered, over high heat to let it come to a boil.
If you are starting with sauce from the refrigerator or freezer, warm it up or thaw it in the microwave. Grate your Parmesan cheese, if needed.
When the water is boiling, add the rigatoni to the pot and give it a stir. Keep the pot uncovered. Set a timer for half the al dente time listed on the package (you will end up boiling the pasta for 5-6 minutes). Have a colander ready in the sink, and stir your pasta occasionally so that it doesn't stick.
While the pasta is cooking, shred the mozzarella cheeses in a food processor, blender, or using a box grater.
After you have boiled the pasta for 5-6 minutes, drain it and add it back to your pot. Stir in two heaping ladles of sauce. (My ladle holds about 1/2 cup.)
Cover the bottom of your baking pan with a ladle of sauce. Add half of the pasta and even out the layer. Sprinkle on half of your Parmesan. Dot the layer with 1 1/4 ladles of sauce. Sprinkle on half of the smoked and regular mozzarella.
Make another layer with the rest of the pasta, the remaining Parmesan, 1 1/4 ladles of sauce, and the remaining mozzarella.
Bake, uncovered, for 25 minutes. Serve with extra sauce and Parmesan, if desired. Cover and refrigerate leftovers for up to five days.
The prep and cooking times listed assume you are starting with sauce already made. If you need to make marinara, it will take another 30 minutes. If you make two batches of Cooking with Mamma C's Homemade Marinara Sauce, you will have extra sauce left over.
You can substitute ziti or penne for the rigatoni.