Cut the skin into small pieces. Use a very good, large, sharp chef's knife.
Place the pieces into a nonstick, deeper pan or a Dutch oven.
Start melting on medium-low heat. Once it starts to melt, reduce the heat to very low.
Melt gently, stirring now and then, until the fat renders and it's golden. And until the cracklings form and turn golden as well. It took me somewhere between 15 and 20 minutes. Cooking time depends on the thickness of the skin and size of cubes, don't overcook. (Note2)
Strain through a fine-meshed sieve. Clean the sieve, line it with cheesecloth, and sieve the fat again into jars. It should be completely free of impurities/sediments.
Place the lids on the jars and let the fat get solid at room temperature. Store in the refrigerator.
Place the cracklings onto kitchen paper, which will remove the excess fat.
Sprinkle with salt (and other spices, if desired) and serve immediately or on the day you've made them.
If you have leftovers, see the blog post for suggestions on how to use them.
The amount is totally optional. Render as much as you have and choose a pan of appropriate size. This amount of skin makes approximately 800 ml/ 27 fl. oz/ 3 ½ cups rendered fat. If the skin is very thick and fatty, you will need about 15-20 minutes to render it. If the skin is thin (like chicken skin), 7 to 10 minutes will probably be enough.