Preheat oven to 450 F. Layout bones on large baking sheet. Roast for 40 minutes, tossing half way through and / or until golden brown.
Add bones and scrape brown bits from the roasting pan into a large pot or Dutch oven (Note: This can also be done in Crock-Pot*, Instant Pot or slow cooker).
Add water until bones are covered (try 12 cups).
For Instant Pot: Close lid and turn knob to seal. Set to cook on low pressure for 3 hours for chicken or 4 hours for beef. When time is up, let the pressure release on it’s own.
For stovetop: Bring to a boil, then reduce to a rolling simmer. You need a high temperature.
Skim foamy bits and impurities that bubble up to the surface. Skim 2-3 times as needed over the first 1.5 hours.
Simmer broth for 12-24 hours. Place lid on top but leave slightly ajar (1-2 inches). Beef needs 20-24, chicken can simmer for just 12 hours.
Add vegetables and herbs for the last three hours of simmer time.
When simmer time is done, remove solids (bones and vegetables) from your pot using spider strainer.
Strain through a fine mesh strainer / sieve
Transfer jars / containers to the fridge to cool.
Remove fat cap from your jars if desired. It works great for cooking.
