2 to 4 eggs
2 x 200g cooking chocolate (one from milk, dark or white - I used dark and white)
180g to 200g biscuit (powdered)
Take the biscuit and put it in the blender, pulverising it until it is no more than powder. Put it to one side.
In a bowl, spoon the mascarpone. Separate the eggs, putting the yolk in the mascarpone and the white in a separate bowl. Fold the yolk into the mascarpone. Whisk the egg white until it is frothy and removing the mixer makes little mounds out of it. I know the photo below lakes the mascarpone look like egg mayonnaise, but it was truly mixed in.
In a saucepan, heat up the dark chocolate until it has fully melted. Take about a third of the mascarpone and put it tinto a third bowl. Pour the chocolate into it and stir until it is totally brown. Put it in the bottom of your presentation bowl.
Take the biscuit crumbs and make a layer on top, flattening it nicely. Then put a layer of sliced banana on top of that. I had a photo but it deleted itself, strangely enough...
Repeat the same thing with the white chocolate and finally the top layer with simple mascarpone, like below. No bananas this time, just a layer of biscuit as above.
Put it in the fridge to set and to give yourself time to realise that this evening you're probably going to have several out-of-body experiences!