Failed the float and the cream sank into the drink. But really, really tasty nonetheless. Minty, chocolaty and rich. I did use Maker's Mark though, with a tiny, tiny dash of banana liqueur to very vaguely approximate the idea of a Jack Daniel's whiskey (yes, heretic, I know!).
This was an excellent dessert drink. All the favlours work well together with nothing overpowering. Had a little issue with getting the float just right, but it worked and was delicious.