Chocolate Crispie Cakes

Technically these should have mini eggs or little fluffy chicks in them, but seeing as I am skint, buying 4 Mars bars for a quid in the co-op seemed frivolous enough.
For some reason, I decided that, rather than just buy one, eat it, feel guilty, get over it and be done with it, buying four on offer would be a good idea. I thought that I would be less likely to eat them all if I made them into crispie cakes. Except that I sort of forgot that I don't have an office of colleagues to feed, and therefore spend most of my time alone in my flat. Unsurprisingly, 12 crispie cakes did not last long.
Damn you, supermarket multibuy offers.

Chocolate Crispie Cakes
Makes 12

4 Mars bars
50g butter
75g rice crispies

Chop the Mars bars into smaller chunks, and place into a large microwavable bowl.
Add in the butter, and microwave on medium for 3 minutes, stopping to stir every minute.
Once melted through, slowly add the rice crispies until all are coated evenly with the chocolate. If they start to get a bit dry, stop adding them, and stir thoroughly.
Scoop up using metal spoons and pop into bun cases. Allow to cool for about an hour, until they set.