Boil the macaroni in a 2 quart
saucepan in plenty of water until tender, about 7 minutes. Drain.
In microwave safe bowl , mix
butter and cheese. Microwave until the cheese melts (stir often).
In a slow cooker, combine
cheese/butter mixture and add the eggs, sour cream, soup, salt, milk,
mustard and pepper and stir well.
Add drained macaroni and
Cook for 3 hours, stirring occasionally.