In Italy's New Year's Eve food tradition, lentils symbolize prosperity when eaten at midnight.
Lentils are commonly served with cotechino, a seasoned Italian pork sausage, or with zampone, a stuffed pig's trotter. Their small, round shape is said to resemble coins, so eating them is associated with wealth and financial good fortune in the coming year.
The custom is especially connected with northern and central Italian cuisine, although New Year's dishes vary across the country. Cotechino and zampone are strongly associated with Modena and the surrounding Emilia-Romagna food tradition. The meal may be served after midnight or as part of the New Year's Eve dinner.
Lentils are not unique to Italy as a prosperity symbol; related customs appear in several countries. The specifically Italian pairing of lentils with cotechino or zampone is the useful clue. The sausage is made from pork, another food traditionally linked with abundance because a pig can represent progress and plenty.