Heat the oven to 425F and spread the raw bones in a single layer on a large baking sheet or roasting pan. Roast for 25 to 30 minutes, until the bones look golden brown and smell deeply savory.

Add the bones, apple cider vinegar, carrots, onions, celery, bay leaves, peppercorns, and salt to a large soup pot or Dutch oven, then pour in filtered water until the bones are covered by 1 inch. Let the pot stand for 30 minutes so the vinegar can begin working before the heat goes on.

Set the pot over medium-high heat just until the liquid reaches a simmer, then lower the heat as far as needed to keep only a few slow bubbles breaking the surface. That lazy bubble keeps the broth clearer and prevents the fat from emulsifying into the liquid.

Leave the lid slightly ajar and cook poultry bones for 24 hours or red meat bones for 48 hours. By the end, the broth should smell deeply savory and the bones should look spent and fragile.

Place the bones, apple cider vinegar, carrots, onions, celery, bay leaves, peppercorns, and salt in the slow cooker and add filtered water until the bones are covered by 1 inch. Let everything rest for 30 minutes so the vinegar has time to start loosening collagen from the bones.

Set the slow cooker to low and leave the lid slightly ajar while the broth cooks. The surface should stay very quiet, with only gentle movement instead of active boiling.

Cook poultry bones for 24 hours or red meat bones for 48 hours. If your slow cooker bubbles too aggressively on low, crack the lid a bit more or switch methods next time for better control.

Add the bones, apple cider vinegar, carrots, onions, celery, bay leaves, peppercorns, and salt to the Instant Pot insert, then pour in filtered water until the bones are covered by 1 inch or the liquid reaches the max fill line. Let the mixture rest for 30 minutes before sealing the lid.

Seal the pot and cook on low pressure for 3 hours if you are using poultry bones or 4 hours if you are using red meat bones. Low pressure helps extract collagen efficiently without rough bubbling.

Allow the pressure to release naturally before opening the lid. The broth should smell rich and savory, and the liquid will often look deeper in color than a quick stock.

Pour the finished broth through a fine mesh sieve and transfer it to jars or other heat-safe containers. The strained liquid should look clean and golden, without bits of vegetables or bone.

Chill the broth until cold, then check the texture and the surface. A successful batch usually turns jiggly and develops a firm layer of fat on top that can be scraped off if desired.