This video is called The History Of Chocolate Part 1 of 4.
From daily The Morning Star in Britain:
Chocolate found on 2,500-yr-old plate
MEXICO: We’ve been eating chocolate for much longer than previously thought, archaeologists have found.
The National Institute of Anthropology and History said traces of chocolate had been found on a 2,500 year-old plate.
Evidence has been found of Mayans drinking chocolate before that date but this is the first proof it was eaten.
See also here.
What Makes Chocolate So Irresistible? A New Study Hints at an Answer: here.
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