The Ham and Cheese Sandwich is a traditional lunch for North American children. It is made by taking two slices of bread, spreading mayonnaise, butter or mustard on them, putting cheese on one and sliced cooked ham on the other, then putting them together. The bread is sometimes toasted. It is commonly given as a "brown bag lunch", but unfortunately, if not refrigerated, the cheese, ham, mayonnaise, and/or butter can spoil.