To answer this question, we must travel back in time to ancient Ecuador, where the cacao tree’s fruits were first consumed by native peoples over 5000 years ago. They consumed cacao in beverage form, but it’s unclear how exactly that cacao was processed or mixed with other ingredients. Chocolate’s original form was that of a beverage, but it likely tasted nothing like hot cocoa. From ancient Ecuador, cacao traveled north to Mesoamerica, where it was domesticated around 3500 years ago.
Mesoamerica is a region of modern-day North America, spanning from central Mexico to Honduras, believed to have been brought together under the rule of the Olmecs. When the Europeans arrived in the 1400s, there were many native cultures within Mesoamerica, but the two larger groups were the Aztec and the Maya. Both groups maintained long traditions of cacao consumption, which it’s believed they inherited from the Olmecs.
Ancient pottery reveals that the product we call chocolate today is almost unrecognizable when compared to the original beverage. Modern mass-market chocolate is more sugar than cacao, while chocolate's original form was the opposite. Modern chocolate has evolved from the Mesoamericans’ deified beverage, which had ingredients added for appearance and ceremony more so than taste. Even its name was the opposite of sweet.Xócoatl, the cacao beverage from which chocolate bars emerged, is best translated from the Aztec language as "bitter or acidic water." (source in Spanish).
Mesoamerican cacao beverages were prepared for both ceremonial and daily purposes, using only cacao beans, water, and spices. Some recipes may have used local honey as a sweetener. The cacao beans used were grown and processed on plantations belonging to peoples throughout the region, so the quality of early cacao was likely inconsistent. Commonly-added spices include annatto, vanilla, and chile, while poorer people also added ground corn to stretch their drink. This is similar to how modern chocolate manufacturers add sugar and cheap oils to chocolate to increase their products’ volume.
The original form of chocolate was more like a chunky herbal tea than a “spicy hot chocolate.” Much of the ceremonially-prepared drink was consumed by royals in the Aztec capital of Tenochtitlan, where Mexico City now sits. Servants would pour the drink from one pot to the other to froth up the fat before serving it. The city was too far north to grow cacao, so the beverage was prepared in a warm but temperate climate, relatively far from where its ingredients were grown. In that sense, chocolate andxócoatl find themselves in a similar role even now— apart from their roots but in a position to go and find them if they so choose.