While wandering through Oaxaca's markets, you'll probably spot large clay basins filled with a liquid that's topped with a beige foam. This is tejate, a drink that dates back to pre-Hispanic times. It's made with cocoa beans, maize, the seed of the mamey fruit, and a flower called "Rosita de Cacao." All the ingredients are ground up to form a floury paste. The "tejatera" mixes it by hand while slowly adding water until it is completely mixed and a thick foam forms on the top.
In Oaxaca city a great place to try tejate is La Flor de Huayapam. It's a stall inside the Benito Juarez market. They have a counter and wooden stools so you can have a seat while you sample the concoction.