Chicken Bone Broth

Preheat the oven to 450 degrees F (230 degrees C). Line a baking sheet with aluminum foil.

Place chicken bones onto the prepared baking sheet.

Roast bones in the preheated oven for 30 minutes.

Gently transfer bones from the baking sheet into a large, heavy stockpot. Add onion and enough water to cover bones by 2 inches. Add vinegar, salt, and pepper and bring to a boil over high heat. Reduce heat to medium-low and simmer, partially covered, leaving enough space for steam to escape, 4 to 5 hours. Check occasionally for froth or foam that develops on top of water, removing it with a large spoon.

Remove from the heat and let cool slightly. Strain broth through a fine mesh strainer into a clean pot. Allow to cool completely at room temperature. Store in the refrigerator and use within 5 days or freeze until ready to use.