BROWN meat in large deep nonstick skillet; drain.
LAYER 1/3 of the spaghetti sauce in same skillet; cover with half each of the meat, tortellini and Parmesan. Repeat layers. Top with remaining spaghetti sauce. Pour 1 cup water around edge of skillet; cover.
COOK on medium heat 20 min. or until tortellini are tender. Top with mozzarella cheese. Cover; cook until mozzarella is melted.