Chocolate is produced from the seeds of a tropical tree called the cocoa or, more properly, cacao tree. As with coffee, the quality of cocoa is sensitive to growing conditions, so cocoa from the best growing regions commands the highest prices. Cocoa trees produce large pods full of seeds called cocoa beans. After the pods are harvested, the beans are quickly removed and allowed to ferment until they lose most of their moisture. There are several ways of doing this, but the traditional method is to spread them between layers of banana leaves and leave them for several days, turning them often so they ferment evenly.
