HHere’s some information in a hundred-year-old cookbook about making cocoa and chocolate. Not quite sure how cocoa differs from chocolate.
Cocoa and Chocolate
Theobromine is the stimulating element in cocoa beans, and is much less pronounced in its effect than the corresponding principles in tea and coffee. The high percentage of fat, together with other food principles, places this bevarage in the class with foods. As a rule, when making cocoa or chocolate, follow the recipes found on the package. It will be well to bear in mind, however, that boiling will greatly improve it. Beating constantly with an egg beater while cooking will thoroughly mix the ingredients and prevent a thin skin from rising to the surface.
Mrs. DeGraf’s Cook Book (1922)