Chocolate appears to have been created at least 3,100 years ago as Central Americans enjoyed a drink brewed for special occasions, according to a report published Monday in the Proceedings of the National Academy of Sciences (PNAS).
Evidence found by a group of archaeologists from Department of Anthropology, Cornell University, "pushes back" the earliest known use of cacao, the source of chocolate, by 500 years.
The archaeologists identified residue of the chemical compound theobromine, which occurs only in the cacao plant, in liquid-holding pottery vessels dating from about 1150 BC.
UPDATE: More here.
UPDATE II: More here, too with a picture/drawing of one of the pots.