Add all frozen raw animal parts to slow cooker.
Add clean fresh water until it is about half way up the frozen ingredients.
Plug in slow cooker, put on the lid and set it to high for a few minutes till it gets warm, then set it to low.
Leave it to cook for 18 - 20 hrs.
Unplug slow cook, leave contents to cool a little.
Take your potato masher and mash up the slow cooked ingredients.
Look for any large bones that will not easily break apart, and discard them ( just to be on the safe side).
Continue to let it cool, once cooled spoon food into glass freezer containers and freeze once the food has completely cooled