No it has nothing to do with Cuba but it was one of my favorite place since they sell amazing alfajores y havanets.
When we visited Buenos Aires it was cold and my friend that's from BA told me they served this drink called "El Submarino" which is basically warm milk and they give you a stick of dark chocolate for you to submerge and whisk until it comes out to a beautiful drink of warm chocolate milk. We also ordered tea and an array of alfajores to get well chocolate wasted.
I would recommend you trying these chocolates and "el submarino" if you're ever around this area. read more