1. Preheat oven to 350 degrees. Boil penne pasta according to package instructions. 2. Heat meatballs and then add to hot pasta. 3. Mix the alfredo sauce with the nutmeg and pour over the pasta and mix, coating the pasta and meatballs. 4. Pour the pasta mixture in a greased shallow casserole dish and sprinkle mozzarella on top. 5. Place in the preheated oven and bake until heated through and cheese is melted and bubbly.