Preheat the oven to 400°F (200°C) and lightly spray a 9x13-inch baking dish with cooking spray.
Cook the rigatoni in a large pot of boiling salted water according to package directions until al dente; drain well.
In a large mixing bowl, combine the cooked rigatoni and ricotta until evenly mixed.
Add the frozen meatballs and the spaghetti sauce to the pasta-ricotta mixture and stir to coat everything evenly.
Transfer the mixture to the prepared baking dish and sprinkle the grated Parmesan evenly over the top.
Pour the Alfredo sauce over the casserole, spreading gently, then top with the shredded mozzarella.
Bake uncovered for 25–30 minutes, until the casserole is bubbly and the cheese is starting to brown; remove and let rest a few minutes before serving.