You should be able to make it with cream and whip it.
When i make whipped ganache, i use 1 cup cream + 1/3 cup chocolate. Melt it together and as it cools i beat it and it goes thick so the cream still has whatever properties it needs to whip even though its been heated.
I would make a runny custard with cream base and then when cool whip it.
ETA - Bakeries use Custard Cream for Eclairs - it would be a similar process http://www.taste.com.au/recipes/12572/choc...h+custard+cream
If you have store bought custard that you are looking to do something with, you could try warming it and adding gelatine and making a cheats Creme Caramel with Caramel Sauce...
Mum use to do this with a big tablespoon of Carmel icecream topping in a cup, topped with the warmed Custard/jelly mix and set in the fridge.
This post has been edited by Working_Mummy: 12/04/2012, 01:17 PM