Roast the bones for 20 minutes at 350ºF. Roast the onion, carrots and the garlic for 45 minutes at 350ºF.
Add all ingredients to a large stock pot and cover with water. Simmer on low for 12 to 48 hours. Cool and strain the broth. Refrigerate until the broth sets and remove the top layer of fat. Portion and use for soups and sipping.