A coin is traditionally hidden inside Greek New Year's Eve cake, known as vasilopita.
Vasilopita is served around New Year's Day in Greece and in Greek communities worldwide. After the cake is blessed or cut, slices are distributed to family members and sometimes to the household, the church, or absent relatives. The person who finds the coin is traditionally said to receive good luck for the year.
The cake is associated with Saint Basil, whose feast day is celebrated on 1 January in the Greek Orthodox tradition. A popular legend says Basil asked wealthy residents to return valuables they had surrendered, and the items were baked into loaves so each person would receive the right object. The historical details of that story are devotional tradition rather than a verified origin account.
The coin is wrapped or positioned carefully before baking. Diners are warned to eat cautiously, since a hard coin hidden in a cake can be a choking or dental hazard.