Preheat oven to 350*. Mix cooked spaghetti, butter, parmesan, and eggs. Place it into a 9 X 13 pan. Spread cottage cheese on top. Cook meat and onions, drain. Stir in tomatoes, sugar, oregano, and garlic. Heat through. Bake for 20 minutes. Sprinkle mozzarella cheese on top, and bake for another 5 minutes. Enjoy!