OK, so this is my Meisterwerk. You can see how glorious it looks and you need to know now how easy it is to make. You just buy some Hallowe'en-themed lollies (I use the jellied kind) which are scarcely hard to find at this time of year and stick them into a slightly babyfied version of a devil's food cake (what else?) made by bunging everything together in the processor.
You'll probably need to go to a specialist shop to get the black food colouring paste (usually labelled liquorice) and the black sugar sprinkles. I also use the cake batter and icing (though without the sugar sprinkles) to make Hallowe'en cupcakes; you should get 12 out of the mixture.
Recipe posted by Nigella