2 pounds (or more) of quality bones (beef marrow and/or knuckle bones)
1 pound of chicken feet, necks or backs
1 or more gallons of filtered water (use one gallon per pound of bones)
2 TBSP (per quart of water) of one of the following: apple cider vinegar, red or white wine vinegar, lemon or orange juice
Place bones in a large stock pot along with vinegar and filtered water. Let the bones sit in the water for 30 minutes. Bring to a boil and skim off any scum that floats to the top. Next reduce to a simmer. Cook your broth covered on a low simmer for 12-48 hours.
Strain your broth through a fine mesh filter lined with a paper towel to catch impurities. Once cooled pour into quart mason jars. Use the broth within 2-3 days or freeze for long term storage.
I use a 5 gallon stock pot to cook my broth. My typical combination of bones is: 2 pounds lamb bones, 2 pounds chicken parts (feet, left over carcass, necks, or backs), 2 pounds beef knuckle bones and 1 pound of marrow bones. I cook my broth for 48 hours.
I use two smaller stock pots and a bowl along with a box fan to cool the broth rapidly after cooking. Don’t put hot broth in the refrigerator. As the outside will cool and the inside will remain hot.