Cacao/chocolate was prepared a bit differently from today's, of course:
- hardly sweetened (sometimes, with honey),
- flavored with various spices,
- prepared as a rather thick, bitter drink,
- foamed up by pouring from one container into another.
Different people/companies are credited with the invention of the chocolate bar (depending on which version one thinks of), but it was already a Mesoamerican preparation that cacao beans would be ground up with spices, formed, and dried. This gives something like a cacao bar, but it was neither sugared, nor even meant to be consumed like that. Rather, it was a way of pre-preparing cacao mass from which to make the usual drink.
Still, even if chocolate bars aren't quite the traditional way of consuming cacao - and the more traditional spicy hot chocolate/cocoa is being re-discovered - the combination of chile pepper and chocolate has been making a sweeping comeback. Sometimes it's a strange one, usually, a very pleasurable affair.
ChiliCult.com - Chile Peppers and Culture