Ingredients:
- 4.5 lbs mixed beef bones (knuckles, patellas, neck bones, and marrow bones)
- 2 large yellow onions, halved with skins on
- 3 large carrots, cut into thirds
- 3 stalks celery, including leaves
- 1 head of garlic, halved crosswise
- 2 tbsp apple cider vinegar
- 2 bay leaves
- 1 tbsp black peppercorns
- 1 bunch fresh parsley
- 6 quarts filtered water
Instructions:
- Preheat oven to 450°F (232°C). Arrange bones in a single layer in a roasting pan and roast for 30–40 minutes until mahogany-colored.
- Transfer roasted bones to an 8-12 quart stockpot. Deglaze the roasting pan with hot water, scraping up the browned fond, and add to the pot.
- Add onions, carrots, celery, garlic, apple cider vinegar, and peppercorns to the pot.
- Cover ingredients with cold filtered water (about 2 inches above the bones). Let sit for 30 minutes to allow the acid to begin mineral extraction.
- Bring to a very low simmer over medium-high heat. Once simmering, reduce heat to the lowest setting.
- Maintain a low simmer (180°F-200°F) for 24 to 48 hours, skimming any foam that rises to the surface occasionally.
- In the final hour of cooking, add the fresh parsley.
- Strain the broth through a fine-mesh strainer lined with cheesecloth. Discard solids and cool the liquid rapidly before refrigerating.