Cook macaroni until al dente. Drain. In casserole, toss macaroni, butter, cayenne, salt, pepper. Mix milk, egg, mustard. Stir into macaroni. Toss cheeses. Mix half with macaroni. Bake 10 min at 350°. Stir in half of remaining cheese, bake 5 more min. Add last of cheese, bake 10 min.
Submitted by Gretchen Grant Contributed on: and modified on Sunday January 30th, 2005