Cook Rotini according to package directions and drain. In a large skillet cook ground beef over medium heat until brown, drain, stir in tomato sauce. Bring to boiling; reduce heat, simmer, uncovered, for 15 minutes, stirring occasionally.
In a small bowl combine dip, cream cheese, and milk. Layer beef mixture, cooked pasta, and dip mixture in a greased 2 quart rectangular baking dish.
Cover & bake in a 350�F oven for 15 minutes. Sprinkle with cheese and bake, uncovered, for 15 minutes more. If desired, top with green onion.