Preheat the oven to 220'C.
Score the skin with a sharp knife in a criss cross pattern.
Rub the salt into all the score marks. The salt draws moisture out which allows better crackling.
Leave for 15 minutes.
Place on a rack in a baking tray and cook in the oven for 10 minutes before reducing the temperature to 160'C. Cook for a further 30 minutes or until the crackling is golden brown and crisp.
Allow to cool before serving.
«Any good butcher will be able to sell you the skin separately to a pork joint for this recipe.»