Cook and drain spaghetti (3 1/4 c cooked). Stir butter, parmesan cheese, and eggs into hot spaghetti. Form into a crust in a buttered 10-inch pie plate. Cook beef and onion till meat is browned; drain fat. Stir in tomatoes, tomato paste, sugar, oregano and garlic; heat. Mix in separate bowl cottage cheese, egg, bread crumbs, spinach, and 1/2 of the mozzarella cheese. Spread over spaghetti. Top pie with tomato mixture. Bake at 350� for 20 minutes. Top with remaining mozzarella and bake for 10 minutes longer (or until cheese is melted & bubbly).