Ice cream cake is a dessert consisting of layers of ice cream and cake pastry. In some cases, the cake doesn't contain cake pastry, so layers of ice cream make up the entire cake. Most often, the cake is covered with soft-serve ice cream that acts as icing, although it can be covered with traditional icing instead of the ice cream.
The dessert is very popular at birthday parties and similar celebrations in North America, although some believe that it originated in England. Its popularity caught on during the 19th century, when ice cream was considered a luxurious item reserved only for the well-off.