Preheat the oven to 400°F (200°C).
Bring a large pot of salted water to a boil and cook 1 lb rigatoni according to package directions until al dente.
Reserve 1/4 cup of the pasta cooking water, then drain the pasta in a colander and return the pasta to a large bowl while still hot.
Add the pesto (about 6.35 oz jar) and 1 cup crushed tomatoes to the hot pasta; add reserved pasta water a little at a time until the mixture is saucy but not watery, then stir to combine.
Spray a 9x13-inch baking dish with nonstick spray. Spread half the pasta mixture into the dish and sprinkle with half (1 cup) of the shredded mozzarella.
Top with the remaining pasta and the remaining 1 cup shredded mozzarella.
Bake for about 20 minutes, or until the cheese is melted and bubbly.
Remove from the oven and garnish with chopped fresh basil before serving.
