[grokx]

Or maybe it is to disambiguate "vert chaud" (hot green) and "verre chaud" (hot glass) that are pronounced the same way. =)

[franky47]

Verte chaude would be grammatically correct, though if there's just a dash of Chartreuse in a cup of hot chocolate, I'd wager the gender of the most statically significant beverage should prevail (Vert chaud).

Also chances are you'd drink those from a mug or cup, not a glass.

[mytailorisrich]

Well that's what happens when you disturb the natural order of things by mixing hot chocolate and Chartreuse ;)