Organic Bones
Braggs Apple Cider Vinegar - 3 Tablespoons
Water
I roast bones for about 20 mins on each side at 400 first. Then put in slow cooker. If you have any veggies to add like celery, carrots, garlic, ginger you may put them in as well for added nutrients. I usually throw in leftovers or discarded bits from other meals. Fill water to just above bones and make sure it stays there throughout cooking. Add apple cider vinegar (this helps bring out the nutrients) and cook on low-med for 24-48 hours. The longer and slower the better.
When finished, remove bones, strain and use, freeze or can.