Nigella's Chocolate Caramel Crispy Cakes

I currently have some mars bars sitting around and I don't fancy eating them neat. I've convinced myself that if I make them into some other confectionary, that it will be less fattening. Anyhow, this is from an old episode of Nigella Feasts which I dug up and hope to try soon!

Ingredients (makes 40)
4 smallish (total 50 g or 2 oz) chocolate candy bars (recommended: Mars Bars or Milky Way)
1/2 stick (50g or 2 oz) unsalted butter
2 1/2 cups (70g) crunchy sweetened corn cereal (recommended: Cornflakes)
Special equipment: approximately 40 mini muffin papers

Method
1) Break the candy bars into bits and drop them into a saucepan. Add the butter and melt, over lowish heat, stirring frequently with a rubber spatula. When everything is melted (the nougat-like layer takes the longest to go), tip in the cereal and turn them, with your rubber spatula, in the chocolate mixture until they are all pretty well coated. 2) Line mini muffin tin with the mini muffin papers. Fill the mini muffin papers with the mixture and put in the refrigerator, on a small sheet pan or tray, for at least 1 hour.