Royal icing gets its shiny appearance from its smooth texture and the way it dries. When properly mixed and applied to cookies or cakes, royal icing forms a smooth surface that hardens as it dries, resulting in a glossy finish. The use of powdered sugar, egg whites or meringue powder, and water contributes to its consistency and sheen.Hey theree!! I've been pondering over what exactly makes royal icing achieve that gorgeous shine we all adore. Does anyone know what to do? I've tried my fair share of royal icing recipes, but I still don't know the secret behind this. Do you have any insights to offer?