To a large skillet over medium heat at the ground beef and onion break the ground beef up and cook it through. Remove any excess grease from the pan.
Spray a 9x13 baking dish with nonstick spray add the cooked ground beef onion mixture in, tortellini, pasta sauce, water, 1/2 cup mozzarella cheese, parmesan cheese, and seasonings stir well.
Sprinkle the remaining cheese over the top cover with foil and bake for 25 minutes. Discard the foil and bake for an additional 20 minutes.