A strong drink of unprocessed cacao, usually with music, sharing and intention setting. Theobromine and a little caffeine produce a mild lift and, for most people, an easier time being emotionally open in a group. It is not psychedelic and anyone telling you otherwise is selling something.
A ceremonial dose is roughly 40 grams of minimally processed cacao, which is a great deal more than a hot chocolate and enough theobromine to be felt. The effect is a warm, slightly wired openness that lasts a couple of hours. It reliably makes group sharing easier, which is most of what the format is for.
The commercial history matters. The modern ceremony as sold worldwide, and the dominant ceremonial cacao brand, were built around San Marcos La Laguna by an American who moved there in the 2000s and who has not run routine in-person ceremonies since 2020. What remains is a village where cacao ceremonies are now ubiquitous and a global brand with hundreds of trained practitioners.
None of that makes it fake. It does mean that if you want the Maya practice rather than the Western format, you have to ask for it specifically and pay a Maya ajq'ij directly, and you will pay less for it, which is itself the problem.
A representative shape drawn from how these are typically run. Use it as something to ask against, not as any one centre's timetable.