PREHEAT oven to 400°F. Mix Alfredo sauce and milk in medium saucepan; bring just to boil on medium-high heat, stirring occasionally. Meanwhile, mix Parmesan cheese, parsley and garlic powder until well blended; set aside.
SPRAY 13x9-inch baking dish with cooking spray. Separate fettuccine noodles; place in prepared dish. Pour Alfredo sauce mixture over noodles; press noodles into sauce to completely coat noodles with sauce. Top with chicken. Sprinkle with Parmesan cheese mixture and the mozzarella cheese.
BAKE 30 min. or until chicken is cooked through (170ºF). Let stand 5 min. before serving.