A croissant (French pronunciation: [k?was?~] ( listen), anglicised variously as /kr?'s??nt/, /kw??'s??n/, etc.) is a buttery flaky bread, named for its distinctive crescent shape. It is also sometimes called a crescent or crescent roll. Croissants are made of a leavened variant of puff pastry by layering yeast dough with butter and rolling and folding a few times in succession, then rolling. Crescent-shaped breads have been made since the Middle Ages, and crescent-shaped cakes (imitating the often-worshiped Moon) possibly since classical times. Making croissants by hand requires skill and patience; a batch of croissants can take several days to complete. However, the development of factory-made, frozen, pre-formed but unbaked dough has made them into a fast food which can be freshly baked by unskilled labor. Indeed, the croissanterie was explicitly a French response to American-style fast food. This innovation, along with the croissant's versatility and distinctive shape, has made it the best-known type of French pastry in much of the world. In many parts of the United States, for example, the croissant has come to rival the long-time favorite doughnuts Croissant pastry can also be wrapped around any praline, almond paste or chocolate before it is baked (in the latter case, it becomes like pain au chocolat, which has a different, non-crescent, shape), or sliced to admit sweet or savoury fillings. In France and Spain, croissants are generally sold without filling and eaten without added butter, but sometimes with almond filling. In the United States, sweet fillings or toppings are common, and warm croissants may be filled with ham and cheese or feta cheese and spinach. In the Levant, croissants are sold plain or filled with chocolate, cheese, almonds, or zaatar. In Germany, croissants are sometimes filled with Nutella or persipan. In Switzerland the croissant is typically called a Gipfeli which typically has a crisper crust and is less buttery than the French style croissant. In some Latin American countries, croissants are commonly served alongside coffee as a breakfast or merienda. These croissants are referred to as medialunas ("half moons") and are typically coated with a sweet glaze ("de manteca", made with butter). Another variant is a medialuna "de grasa" ("of lard"), which is not sweet.