Combine cottage cheese, milk, mustard, cayenne, nutmeg and salt and pepper together in a bowl using a whisk. Reserve 1/4 cup grated cheddar for topping. In a large bowl, combine the rest of the grated cheese, milk mixture and uncooked pasta. Pour into a buttered 9-inch baking pan, cover tightly with foil and bake 30 minutes.
Uncover pan, sprinkle with remaining 1/4 C cheddar cheese and dot with butter. Bake 30 minutes more uncovered, til brown on top. Let cool ~ 15 minutes. Enjoy!