Preheat oven 350˚ F.
Brown ground beef over medium heat with onions. Drain fat. Stir in tomato sauce, sugar and set aside.
Boil the pasta according to package directions and drain. Set aside.
In a bowl, combine cheeses, sour cream, green onions, green pepper, salt, pepper and garlic pepper. Set aside.
Spray a 3 quart casserole pan with cooking spray.
Add half of the meat mixture to form the bottom layer.
Layer with half of the pasta.
Cover with all the cheese mixture.
Layer with remaining pasta.
Top with remaining meat sauce and sprinkle with shaved parmesan.
Bake at 350˚F for 30 minutes. Serve warm.