The best bit of roast pork is the crackling. That is what we fans of crackling say, although it cannot be quite true - pork without crackling would be preferable, surely, to crackling without pork. But it is certainly the treat that lifts the whole meal. My problem is that my success rate when cooking it is about 30 per cent.
The frustrating thing about a culinary shortcoming is that the advice of experts rarely cures it. You can follow their instructions devotedly, only to find that what produces perfect results for them will not work under your own, amateurish hands. So it is with me and rice; and so it is, more often than not, with me and crackling.
For example, Richard Ehrlich, author of the invaluable The Perfect . . . (Grub Street), says that you can get the crackling process started by holding the joint, skin-side down, in hot oil. That has never worked for me. I have tried, too, putting the joint under the grill before roasting it, also without success.
Do you need oil at all? Most writers say yes. A few believe it to be unnecessary: the layer of fat under the skin, they think, should perform the necessary crisping. To encourage it, you score the skin first - or, preferably, get the butcher to do it - with a Stanley knife. Some enthusiasts encourage the skin to contract by pouring boiling water over it. The risk in this procedure, I should imagine, is that you melt and disperse some of the fat, which you want to keep.
A mass-produced joint of pork, sweating under polythene, is never going to crackle. You want a free-range cut with a thick skin, and you have to get the skin dry. Keeping it in the fridge uncovered is a good idea, so long as it is well away from other foods. You can wrap it in a dishcloth, but not in clingfilm.
Some time before cooking, wipe the skin with a paper towel. Rub salt into it. After a while, beads of moisture will appear. Dry the skin again. Now, either rub a little oil on to it, and salt it again; or apply the salt alone. I am not sure which option to recommend. Most recently, I left out the oil, and - on this occasion - it worked.
If you have a small joint, you need to kick-start the crackling process. I put mine (650g) into a gas mark 8/230°C oven for half an hour, and then reduced the heat to 2/150°C for a further 45 minutes. Some writers tell you to turn up the setting at the end; but, though you can get away with a high temperature at the start of cooking, you risk drying out the meat if you give it a blasting now. Instead, take it from the oven, put it on a warm plate and remove the crackling. Lay the crackling back in the roasting tin in the oven and set to high again. You need to keep an eye on it. Meanwhile, the pork will benefit from a rest, perhaps covered in foil.
I can do all that and still produce inedible rubber. But perhaps you, following these recommendations, will fare better with them.