Preheat oven to 350 degrees. Lightly grease a 9×13 baking dish with non-stick cooking spray.
Cook the tortellini according to package directions. Drain.
Add the drained tortellini to the baking dish that's been sprayed with non-stick cooking spray, and then add the tomato sauce.
Stir gently to combine.
Add 1 cup of the mozzarella cheese and ¼ cup Parmesan cheese.
Stir gently to combine.
Top with the remaining 1 cup mozzarella cheese.
Bake until the sauce is bubbly and the cheese melts, 20 to 25 minutes.
