I wanted to get the batter right. Having failed with the deep fried pickles, I wasn't going to make the same mistake twice. I used a recipe of flour, cornflour, baking powder, milk, and beer. Make a nice thick batter, dip in a chilled mars bar, and plonk straight into hot oil.
I knew the batter was good, as it puffed up, hardened, and went golden within a few seconds. It looked bloody brilliant. I ate it with vanilla ice cream and chocolate syrup (drizzled artistically, of course).
It really does taste a lot better than you'd think. Sickly and rich would be an understatement, and eating a whole one is a bit of a challenge. But a worthwhile endeavour nonetheless. I would suggest NOT chilling it first, if you want the inside to melt and go runny - only chill it if you want the bar to remain relatively solid.