Bring a pot of water to a boil and add tortellini; cook for 7-9 minutes until tender. Drain, rinse with cold water, and set aside.

Pour pasta sauce into a large saute pan and heat over medium till hot. Add tortellini and gently stir into the sauce.

Pour pasta and sauce mixture into a 9x13 baking dish. Sprinkle grated mozzarella cheese evenly over pasta. Set the oven to broil and place baking dish in the oven. Heat until cheese is melted. Serve hot.