Preheat oven to 350. Prepare a 8" square casserole dish with cooking spray; set aside. In a large saucepan, cook chicken and onions until chicken is no longer pink. Add tomato sauce, salt, basil, and black pepper. Bring mixture to a boil. Meanwhile, combine cooked noodles, cottage cheese, and sour cream. Mix well. Spread half of the noodle mixture onto bottom of prepared dish and top with half of the chicken mixture; repeat layers once. Sprinkle top evenly with cheese. Bake, uncovered, for 30 minutes, or until cheese has melted.