This is my favorite way to make Macaroni and Cheese. It is super easy and tastes delicious!
3 cups cooked macaroni
1 tablespoon butter or margarine, melted
3 cups shredded sharp processed cheese
2 cups evaporated milk
1/4 cup chopped onion
1 teaspoon salt
1/4 teaspoon black pepper
Toss macaroni with butter or margarine. Add remaining ingredients. Pour into lightly greased Crock-Pot. Cover and cook on High 2-3 hours, stirring once or twice.