A sweet spread that is applied to cakes, pastries, and cookies. It is also called icing and can be prepared with a number of different ingredients. Sugar or powdered sugar is the ingredient that is common to all frosting, but other ingredients may include butter, milk, eggs, water, cream cheese, and flavorings such as vanilla or other extracts. There are cooked and uncooked varieties of frosting. Regardless of the type of frosting, they must be thick enough to stay in place once they have been applied, but they also must not be so thick that they cannot be spread easily.