Decorating sugar is a product used primarily on top of baked goods such as cakes and muffins to add sweetness to the dish and to also add color. It is quite common for this type of colored sugar to be sprinkled over cakes that have already been topped with icing. There are dozens of colors of decorating sugar that can be used in order to match or stand out in contrast to the color of the icing that tops baked goods. Depending on the skill of the pastry chef, decorating sugar also can be used to create patterns on tops of cakes and cupcakes.
The instances in which decorating sugar is not used along with icing are usually with cookies. Sugar cookies, for example, may be coated with decorating sugar to create a splash of color on the top of the cookies or to even make a shape. For example, sugar cookies made for the Christmas holidays may be topped with green colored sugar that is arranged in the shape of a Christmas tree. Sugar cookies that are made for Valentines Day may be topped with red or pink sugar — or a mixture of the two — that is arranged into the shape of a heart.
In order to get decorating sugar to adhere to cookies, it is best to add it to the tops of the cookies while they are fresh out of the oven and still warm. Unlike iced cakes and cupcakes, cookies don't have a sticky substance on the top that will hold the sugar in place. As such, the sugar must be added when the cookies are still warm enough so that the crystals can become slightly embedded in the tops.
Decorating sugar can be bought in most grocery stores but is also pretty easy to make at home. Simply fill a clean plastic bag with the desired amount of sugar and add a few drops of food coloring. For custom colors, a few different colors of food coloring can be added.
Knead the plastic bag with the sugar inside until the sugar has absorbed the food coloring and is uniform in color. To make this process as easy as possible, be sure to add the food coloring drops in different areas of the plastic bag so that the color does not become concentrated in one area. Homemade decorating sugar can be stored just like plain sugar.