Will write on any food surface firm enough to write on. * The Gourmet Writer Food Decorating Pens are great for a fun, fast way to add dazzle to fondant cakes, cookies, and all kinds of food. * Use these edible color markers just as you would an ink marker * Draw fun designs on cakes, write messages on cookies, and highlights to icing decorations. * They are also great for cheese, fruit slices, and bread.