Dead simple - line a loaf-tin or brownie pan with thinly sliced all-butter madeira cake, then raspberries, then good vanilla ice cream (I used Green and Black's), more raspberries, then a final layer of thinly sliced madeira cake. I sprinkled the cake slices with maraschino liqueur in order to add a bit of extra moisture. Cover with clingfilm and return to the freezer until ready to eat, in slices, with icing sugar over the top. Next time, I might make some raspberry puree to go with it, just for a bit more welly! The online recipe, by the way, doesn't specify the raspberry addition - I would definitely add them, for colour, flavour and texture.