Cut suet into small chunks using knife, food processor or meat grinder
Add suet to instant pot or slow cooker and turn on low.
Render for 6 to 8 hours, stirring a few times in the first hour to make sure suet is not burning.
Strain cracking from liquid suet using fine mesh strainer and cheesecloth, if using.
Put a lid on the jars and leave on the counter until cooled and has turned white.
If you aren't planning on using the tallow within a couple weeks, I would recommend using the cheesecloth inside of the metal strainer. This assures that there are no solids left in the tallow that could cause it to spoil quicker.