~150 years ago in Eastern Europe, the Kitzur Shulchan Aruch wrote that you could usually go buy a coffee, tea, or hot chocolate without having to worry about its kosher ingredients (or bishul akum). While this is mostly our practice today with regards to unflavored coffee or tea, I assume the hot chocolate available then was purely vegan; and today everyone would demand a hechsher on their hot chocolate given the possibility of animal-based flavorings, marshmallows (=gelatin), and the like.
Is there anywhere in the world (barring the use of a time machine) where you can still get a plain hot chocolate without a hechsher?