It is easy to render lard with little to no hands-on time. Lard is a healthy animal fat used for frying, sauteing, and many pastries, giving them their flaky texture. It contains both saturated fat and cholesterol which, despite what we were told in the 1980s and beyond, can be good for you and does NOT raise your risk of heart disease. You can find a great article about the virtues of lard at Empowered Sustenance.
To render lard is to melt pork fat and separate the fat from other tissues, leaving you with a tasty, clean, lard. I highly recommend sourcing either leaf lard or back fat from pastured pork if possible as it will be higher in omega-3 and lower in polyunsaturated fat. For now, I get mine from a local butcher though eventually, we hope to raise our own.
Turn your slow cooker on low and place your fat in the cooker. I usually fill my cooker at least half full. Chopping up the fat will make it render faster, but increases your hands-on time, so do what works for you.
Allow it to render out for 12 hours or overnight. In the morning, carefully ladle your lard through a coffee filter, into your container. Continue to heat the fat until what is left in the pot seems crispy. Filter the rest of the fat and then dispose of the rest. Sometimes we give it to our chickens. They LOVE it.