Serving suggestion: Microwaved Jaffa Cakes are mighty fine fare - give one a blast for not longer than 10 seconds (at the most) and it becomes a different beast.
What happens is that the biscuit base part stays exactly the same temperature (because it doesn't contain any water), but the orange jelly becomes lovely and gooey and the chocolate melts. Try it, it's great.

Warning: Because the base is cool you can easily have a Microwave Jaffa that has napalm-like jelly but appears to be cold.
This leads to nasty burning of the roof of the mouth.