Today is the Cold Foods Festival in Vietnam, or Tet Han Thuc. The festival started in China, where it is associated with a legend that forbids cooking on this day. Vietnamese people cook as usual on this day but make offerings of sticky rice cakes called banh troi (floating cakes) and banh chay (lean cakes) to their ancestors and the Buddha. These cakes, which resemble round white eggs, are associated with Vietnam’s founding myth about a mountain fairy, Au Co, who married a sea dragon, Lac Long Quan, and gave birth to 100 eggs. From these magical eggs hatched 100 sons who became the forefathers of the Vietnamese people.