BROWN meat in large saucepan. Stir in spaghetti sauce; simmer 5 minutes, stirring occasionally. Remove from heat. In a separate bowl, mix egg, cream cheese, sour cream, and parmesan together.
LIGHTLY coat bottom of 13x9-inch baking dish with spaghetti sauce mixture. Top with layers of 3 noodles, 1/3 of the cream cheese mixture, then with 1/3 spaghetti sauce mixture, then 1/3 pkg. mozzarella and 1/3 pkg. cheddar. Repeat for 3 layers. Cover.
BAKE 30 min. or until heated through. Uncover. Bake, uncovered, 15 min. or until cheese is golden. Let stand 5 min. before serving.