Cocoa Powder & Ready Mix
The cocoa bean, also cacao bean or simply cocoa or cacao, is the dried and fully fermented fatty seed of Theobroma cacao tree, from which cocoa solids and cocoa butter can be extracted. They are the basis of chocolate, as well as many Mesoamerican foods such as mole and tejate.
Compared to sugar, cocoa is expensive and not sweet, hence most of the ready to go chocolate beverages comprise mostly sugar and only very little cocoa powder.
Furthermore the pure cocoa powder does not dissolve in water very well. The old fashioned way is to heat up a little bit water or milk in a pot, and whisk the cocoa powder in. You will get a concentrate and you can dissolute it with hot or cold milk, some like a mix of milk and water.
Since the cocoa concentrate is not sweet, best way to sweeten it is to add some sugarcane and if you like a hint of real bourbon vanilla (not that synthetic vanillin and other chemical vanilla flavors), available dried or as a concentrate in a bottle.
Try it out if you have the time, the result will suprise you flavorwise.