The best cocoa beans come from farms on which the cacao is grown and processed properly. That said, the question of the best cacao origins has a complex answer. There are places where all the cacao grown there is of similar high quality varietals, like Grenada. But to say that all Grenadian cacao is good just because it comes from a more highly-regarded varietal is like saying all arabica coffee is good. It’s not.
The post harvest processing of cacao is even more important than the type of cacao itself. That’s the point at which much of chocolate’s flavor potential is developed. You can find high quality cacao from almost every tropical country in the world. Bulk cacao and fine flavor cacao are grown side by side in many parts of the world, such as the Philippines or Ecuador. But there is a difference in reputation between the cacao from many countries.
Rare cacao varietals such as Nacional and Porcelana have been found in parts of northern South America, and many people regard those as some of the best cocoa beans in the world. The Caribbean island of Trinidad only grows trinitario cacao, a highly flavorful type of cacao developed on the island hundreds of years ago. The best cacao origin then comes down to your own personal preference for certain flavors over others, and your ability to hunt down the best chocolate.
Both bulk cacao— also called commodity cacao— and fine flavor cacao can be grown in most any cacao growing region around the world. All cacao needs proper shelter and inputs in early life, and appropriate sunlight and maintenance as it ages. Even the most flavorful and smooth cacao varietals could end up as bulk cacao if they're not properly cared for and processed.
Bulk cocoa is a mix of fermented, partially fermented, and unfermented cacao, dried and sourced from small farms across any given region. These beans are usually fermented by each farmer individually, so flavors and varietals are mixed with no regard to quality or bean size. Sometimes the beans come from unripe fruits, as farmers can only afford to harvest their cacao once a month and want to cut the fruits before small animals get to them. Most bulk cacao is of forastero varietals, grown for their higher productivity and larger bean size rather than their flavor.
Fine flavor cacao is often of criollo or trinitario heritage, but since cacaos constantly cross-pollinate, after a few generations most trees on a healthy farm are of mixed heritage. Either way, fine flavor cacaos must be treated with care from the beginning of their lives, shaded and pruned when necessary, and well irrigated and fertilized. For cacao to taste best, producers must only pick the ripe pods to process into dried beans.
Fine cacao from the ripe pods is then properly fermented and dried to around 7% moisture content. After that, fine cacao is often kept in a temperature-controlled environment for storage before being tested and then shipped to makers. A cut test of beans randomly chosen from the shipment can determine the quality of the cacao. More purple-hue beans indicate under-fermentation while grey beans indicate over-fermentation or mold.
Tasting the cacao directly from the bag can hint at the flavor complexity of the cacao, which will contribute to its potential as a fine flavor cacao. The work put into growing and processing fine flavor cacao vs commodity cacao is much higher, and in return, so are the profits. It's not a coincidence that fine flavor cacao can cost five to ten times more than commodity cacao, with even higher prices for rare varietals or origins or processing methods.
While fine flavor or bulk cacao speaks to the quality and often the price of cacao, it says nothing of how, where, or through whom that cacao was sold. Neither direct trade nor fair trade is associated with either grade of cacao. In fact, some high quality cacao is often mixed in with commodity cacao due to lack of market. While ideally all fine cacao would fetch a high price, the reality is that right now, there's still more high quality cacao on the market than buyers of said cacao.
Much fine flavor cacao is being sold as bulk cacao, and if the situation doesn't even out soon, it will reverse before we know it.