1. Mix all ingredients except pasta shells and spaghetti sauce. Fill each pasta shell with about 2 tablespoons cheese mixture.
2. Arrange stuffed shells in circle around edge of pie plate, 9 x 1 1/4 inches. Pour spaghetti sauce over shells. Cover tightly and microwave on high 6 to 7 minutes, rotating pie plate 1/2 turn after 3 minutes, until hot.