Give your cookies the royal treatment by decorating them with a perfect batch of this fast and easy-to-make Wilton royal icing mix. This mix takes the guesswork out of getting the ideal consistency icing for your decorating project. Just follow the directions by adding water. Make thin or flood consistency icing for sugar cookies or prepare it to stiffer consistency for piping standup flowers, petals and borders. The icing dries hard so your cookies are easy to stack and store. It's also the perfect icing to build and decorate gingerbread houses for the holidays. Icing can be stored in the refrigerator for up to 5 days after you make it.