As per the above recipe....cut the mars into 1" chunks and make up a tempura batter....don't seive the flour and only whisk it lightly to get the lumps which turn crispy. Ice cold (and could be fizzy) water is essential.
Curiosity. I have never tried them before and they dont make them down here in London. I suppose that the same batter recipe can be used to deep fry a Snickers bar as well :P
Go to Scotland, they are a speciality up there,
my wife was horrified to know that's what we eat, she almost passed out when the lassie in the chippy explained how to make the Easter special deep fried cadburys cream egg. In fact I think that's why she imsisted we move to England
According to my local chipshop which serves them, the most important thing to do is to freeze them before battering and frying them.
They say they have had loads of children coming in saying that they tried to recreate them at home and ruined the deep fat fryers as they did not know to freeze them first!