This isn’t the usual recipe post but I’ve had queries from a few people asking how I get my crackling to crackle every time so I thought I would dedicate a recipe slot to it. After all, there’s nothing better than a chunky piece of crackling to complete your roast dinner.
I’ve been cooking regular joints of roast pork for Chris and me, sometimes every week for a month or more, for the last two years and I’ve not yet had one that hasn’t crackled. I might have a joint where part of the skin doesn’t crackle and I’ve got to the point where I can predict when that will happen and either do something about it or know that it’s going to be the case because of the size/shape of the joint and expect an uncrackled area instead.
Of course, the real key to my crackling is Delia Smith. Without her Complete Illustrated Cookery Course book, I would probably never have cracked crackling (if you’ll excuse the pun), so the points below come very much courtesy of Delia with a few added points from my own experience.
A golden rule
Before I start on my tips, arranged in cooking order, I have one golden rule. Pork is one joint that you can’t prepare in advance and leave in the oven to cook on a timer setting. If you want to do that, remove the skin with its fat and cook it separately to create the crackling, using the method set out in my spicy pork scratchings recipe (though you don’t need to worry about the spicy topping, just follow the method). You’ll need to add fat to the pork joint to cook it if you do it this way too.
With roast pork you want the skin to be really dry and you’ll see that, with the necessary preparation method, it would no longer be dry if you prepared it and then left it sitting in the oven for a while before the heat actually came on.
Preparation of your joint – 3+ hours before roasting
Preferably you should start preparing your roast pork the night before, but I know many people, like me, are far too busy and only think of this on the day.
At least 3 hours before roasting the joint remove it from any wrapping and leave it standing out on the counter top with the skin exposed. I usually unwrap it from its plastic wrapping in the morning and, depending on the temperature, either stand it uncovered in a bowl in the fridge before moving it out onto the countertop 3-4 hours before cooking or, preferably, just leave it out all morning too.
What you are trying to achieve with this step is bone-dry skin. Drier than you can ever achieve by just mopping it down with kitchen towels. I think it also makes a difference to have the joint at room temperature when you put it in the oven too.
Delia recommends taking the wrapping off as soon as you get the joint home and keeping it uncovered in the fridge. If you have the space to do that then great, but the way things get tightly squeezed into our fridge at home and shuffled about for the few days between shopping day and roast dinner at the weekend this would guarantee blood over everything, so I just ensure enough hours out on the table to allow the skin to completely dry out.
Preparation of your joint – 20 mins before roasting
If you didn’t get your joint from a butcher (who you can ask to score the skin well before selling it to you) then you will need to score it yourself. If it came from a supermarket and looks scored you are well-advised to re-score the skin anyway – I always buy my joints from the supermarket, they always have scoring on the skin but I find that often it’s not deep enough, some sections of the skin missed the blade and all sorts of other haphazard things have happened with it.
Warning – if you don’t want to lose fingertips or just get really frustrated with this you’ll want a really good sharp knife to score the skin!
You want tram lines over the skin of the joint – I cut mine about finger-width apart because that’s the width the supermarket lines are. Most people would probably go for something closer to half an inch apart but I work with the pre-cut lines because it saves me some effort. With the small joints I cook for us it also means plenty of thin ribbons of crackling rather than two big pieces each too.
The structure of pork is that below the skin, which I find varies from 1-3mm thick depending on which part of the pig it came from, there is up to an inch of fat before you reach the pink meat. You need to slice through the skin and also the fat. Many people suggest that you should only cut halfway down through the fat but I cut all the way through it. Sometimes I can judge that I’m about to hit the meat and I will stop but sometimes it will be possible to see the pink of the flesh.
As an interesting side note the pig, along with humans and other pachyderms and aquatic mammals have the fat under the surface of the skin adhering to the skin rather than to the muscle. So, for example. If you skin a rabbit you will find that the skin comes away with relative ease and any fat is left behind on the meat, but try to skin a pig (or a human, presumably) and the fat will come away adhering to the skin. This is what makes it so easy to remove the skin with its fat in order to make crackling or pork scratchings separately.
If it’s the first time you’ve done this, you may want to allow more than 20 mins and I have to admit that the best way to be sure this is done in time is to do it when you first take the joint out of the wrapping. I just prefer to be working with the skin when it’s dry. I can keep a more stable hold on it with my non-cutting hand.
Preparing to cook – 5 mins before roasting
Get your oven on and heated up! 245C (gas mark 9 or 475F) is the best temperature to use and you want it blasting that heat level out as soon as you put your joint in. You definitely don’t want your joint to have time to think about sweating water out of the skin before it gets hot enough to start crackling up.
Make sure you have a shallow-sided roasting tray ready too, or if it has higher sides then it had better be big enough that you can sit the joint in the middle and it is well away from the sides. Otherwise there is a risk that the sides of the pan will prevent the skin on the sides of the pan from being properly exposed to the heat.
Preparation of your joint – 5 seconds before roasting!
Place the joint in the middle of your roasting tray skin-side up and as exposed as you can manage. Then get some ground salt and sprinkle it liberally over the skin. You need to be very generous with your salt and I tend to then put some in the palm of my hand and on my finger tips to rub it onto the more sloping sides to make sure the skin is covered in salt everywhere.
Don’t add any fat to the joint or to the skin. The fat will quickly start leaking out of the joint once you put it in the oven to provide fat for the meat to roast in and any fat added to the skin will prevent it from being dry and able to crackle.
You need to do the salting quickly, not take your time over it – this isn’t an exact science, you just want the best liberal coverage of the skin that you can sensibly manage. Then you need to get it into the hot oven as quickly as possible. As soon as the salt gets onto the skin it will start drawing moisture out of the skin and will quickly undo the drying you achieved by standing the joint out for a few hours.
I do remember once salting the skin and then realizing I hadn’t put the oven on so it was still cold. I then spent most of the time while the oven heated up painstakingly rubbing salt and moisture off the skin with kitchen paper trying to keep it as dry as possible until the oven was hot.
Delia recommends roasting pork at 245C for 20 minutes and then dropping the temperature to 190C and continuing to roast the joint for either 35 minutes per pound (450g) for leg or loin joints or 45 minutes per pound (450g) for any other cut of meat. These cooking times have certainly worked for me and this quick blast of heat at the beginning not only helps seal moisture into the joint but also seems to cook the crackling. It is usually almost completely crackled by the time I reduce the temperature.
Problem areas and fixes
Every so often I get near the end of the cooking time and a quick tap on darker coloured parts of the skin with a fingernail reveal that they haven’t crackled properly. Do always try tapping it with a fingernail because it sometimes doesn’t have that bubbly, pale colouring but has actually crackled.
Uncrackled patches often also look quite “damp” or fatty which is probably why they didn’t crackle. The easiest solution for this, if you’ve checked at least 20 minutes before the end of cooking time is to get a piece of kitchen paper and try to mop up the fat or moisture since it is never too late to get it to crackle if the conditions are right.
Other things that may prevent it from crackling are:
- being too close to the sides of the roasting dish so that the heat can’t get to the skin properly
- having skin that curls under a lip so that the moisture is dripping down through the skin and keeping it moist, and
- for joints with skin that curves round the sides but have a lot of fat I find that the fat melting out of the skin higher up will run down the joint and stop the skin on the sides from staying dry – this last one can be fixed by laying the joint out in a way that keeps these elevated and level with the rest of the joint (perhaps if there’s no easy way to do this raise the skin like big flappy ears and place a half potato or something under it!) but scoring it deeply can help keep the fat in the tramlines rather than on the skin surface.
I hope this helps a few people. Best of luck with your crackling and I’d love to hear if anyone has any other tips for guaranteed crackling!