Lasagna, a pasta dish of Italian origin, is often made with ruffled noodles and tomato or white sauce. Lasagna, in the singular, is a southern Italian variation of northern Italian lasagne, in the plural. The name is thought to come from Ladinum, a Latin word for cooking vessel, although some sources refer to it as the Greek flatbread lagan, which dates back to at least the time of Augustus Caesar (63 BCE−14 CE) in Italy.
Known from Lasagna in its modern form, made with a meat sauce such as ragù Bolognese with noodles and béchamel (besciamella or balsamella) sauce, is believed to have originated in the Emilia-Romagna province. Variations occur throughout Italy: lasagna served in Naples, for example, usually consists of small meatballs, ricotta, mozzarella cheeses, and sliced hard-boiled eggs, while those served in Genoa Pesto is used as a sauce. Some recipes use sausage as well as other types of ground meat. Others add mushrooms to the ragù.
a southern term commonly used because most Italian-Americans trace their origins to southern Italy — follows the Napoleonic template, but with many variations. For example, a vegetarian version will replace the meat with spinach and sometimes other vegetables such as peppers and squash. In Italy, noodles known as lasagne Verdi are made with spinach as an ingredient.
Making lasagna is a more labor-intensive process than other pasta. Lasagna noodles are cooked al dente (firm but not hard) and then drained and cooled, so they can be handled. In an ovenproof dish, a layer of tomato sauce is spooned and then rolled lengthwise with a layer of overlapping noodles.
Layers of meat sauce, cheese, béchamel, or other ingredients are added, topped with another layer of noodles, and repeated. Italian cooks believe that lasagna should have at least three layers of noodles, although four layers are more common. The assembled lasagna is then baked at 350 °F (180 °C) for about half an hour. To keep lasagna moist while cooking, most cooks cover the dish with aluminum foil.
Lasagna is considered one of the oldest pasta dishes in Italian cuisine, attested in medieval literature shortly after Marco Polo returned from his travels in Asia. Polo himself mentions eating a dish in China that he called lasagne, noting that the flour used for the noodles was breadfruit.