Whenever we, or someone we know, have a pig slaughtered we always ask for the fat to make lard. Rendering lard is quite easy and nothing makes better doughnuts than homemade lard.
We follow the directions in Stocking Up: The Third Edition of America's Classic Preserving Guide
Start with your pieces of fat and cut into 1/2" cubes. Put about 1/4" inch of water in a large heavy bottom kettle and add your cut up fat to it, being careful not to fill the kettle too full; it is better to add to it as it cooks. Keep the burner on as low as it will go. A wood cook stove works well for this, as you can slide the kettle around to get the heat you want. You want it to melt, but not scorch.
It takes a very long time for the fat to melt; we have been as long as 4 days to get all our fat cooked. Be sure to stir frequently to mix in the new fat and to keep it from sticking. Patience is needed.
As the lard renders, the cracklings, which are the pieces of fat that do not cook down, (why, I do not know) will float to the top and eventually sink to the bottom. That is when it is time to jar your lard. (The temperature will be about 255o F)
Sterilize your jars, strain the cracklings, and pour the strained lard into your jars, filling to the top. Chill as quickly as possible to produce a finer grain shortening (we set our jars outside….for us, lard making is always done in the fall for a few reasons; it is usually the time people slaughter their pigs, the wood stove is going and it is cool outside)
Store the finished lard in a cool dark place.
Many people enjoy the cracklings (the part that didn’t cook down that was strained off before bottling) and eat them with some salt or as bacon bits. We haven’t really enjoyed them too much, but are still hoping to find a use so they do not go to waste.