Cook the macaroni as directed on the package. Rinse with cold water and drain well.
In a bowl whisk together the evaporated milk, milk, egg, and butter.
Place the macaroni into the crockpot. Pour the milk mixture over the macaroni. Add the processed cheese and 1 1/2 C of the shredded cheese. Stir to incorporate the cheese into the macaroni mixture.
Cover and cook on low for 3 hours or until the center is set, stirring halfway through the cooking time. Sprinkle the remaining shredded cheese over the top and heat 3 minutes or just until the cheese begins to melt.
Makes 8 servings
Notes
Make this macaroni and cheese a little lighter by using reduced-fat evaporated milk, skim milk and 1/3 C of egg substitute in place of the above ingredients. To add a little flavor to macaroni and cheese add crumbled crisp cook bacon.