Cake is a form of bread or bread-like food. In its modern forms, it is typically a sweet bakeddessert. In its oldest forms, cakes were normally fried breads or cheesecakes, and normally had a disk shape. Determining whether a given food should be classified as bread, cake, or pastry can be difficult. Modern cake, especially layer cakes, normally contain a combination of flour, sugar, eggs, andbutter or oil, with some varieties also requiring liquid (typically milk or water) and leavening agents (such as yeast or baking powder). Flavorful ingredients like fruit purées, nuts, dried or candied fruit, or extracts are often added, and numerous substitutions for the primary ingredients are possible. Cakes are often filled with fruit preserves or dessert sauces (like pastry cream), iced withbuttercream or other icings, and decorated with marzipan, piped borders or candied fruit. Cake is often the dessert of choice for meals at ceremonial occasions, particularly weddings,anniversaries, and birthdays. There are countless cake recipes; some are bread-like, some rich and elaborate, and many are centuries old. Cake making is no longer a complicated procedure; while at one time considerable labor went into cake making (particularly the whisking of egg foams), baking equipment and directions have been simplified that even the most amateur cook may bake a cake.