My pregnant wife's cravings have recently turned towards sweets, and this week it is banana splits, with a very specific formula: chocolate ice cream, banana, whipped cream, and hot fudge.   It's not such an extraordinary recipe, I suppose, but the hot fudge is simply not a topping we keep in our house or really have a lot of experience with. So after picking up a jar of hot fudge topping, and zapping it in the microwave, per the instructions, I experienced the obvious result that has presumably been experienced by millions before: hot fudge melts cold ice cream.  Rather quickly, the sundae disintegrated into a soupy mess at the bottom of the bowl, with a rapidly decreasing scoop of ice cream bathing in the pool, and banana bits swimming about. It was not a pretty sight.  What means could I take to mitigate the fudge's effect on the ice cream, or are my wife's hopes and expectations just a dream in the shadow of this bleak reality? 
I think isolating the fudge could be a good way to fix this. It might complicate your dish, but it might add both to the presentation as well as to the texture of the ice cream.  Try getting hold of or make your own biscuit rolls (I don't know the name). Fill these up with hot fudge. The biscuit will act as isolation keep the texture of both the ice cream and the fudge. In this way the only time the two will get in contact with each other is when one breaks up the biscuit to eat it.  If biscuits doesn't cut it, chocolate tubes or similar could do the same trick. 