6-8 large floury potatoes, such as maris piper, king edward, desiree (depending on how hungry you are)
salt and freshly ground black pepper
225g/8oz self-raising flour, plus extra for dusting
beef dripping or oil, for deep frying (beef dripping is used in the traditional method and gives a far better flavour, but sunflower or vegetable oil will work just as well)
4x175g/6oz thick cod or haddock fillets, taken from the head end rather than the tail end of the fish
300ml/10fl oz fridge-cold lager