Chicken Bone Broth

Spread chicken bones and carcasses in a single layer on a heavy rimmed baking sheet. Add halved onion (cut-side down) and carrot pieces. Roast at 220 C (425 F) for 35–45 minutes, turning once, until the bones are deep golden-brown with dark edges and the onion is caramelized black on the cut face. Dark coloring means Maillard flavors — these give bone broth its depth. Do not skip this step; unroasted bones yield a pale, thin broth.

Place roasted bones and aromatics in a large stockpot or slow cooker. Add celery, garlic, vinegar, bay leaves, peppercorns, and thyme. Cover completely with cold water. The vinegar is key — even one tablespoon creates an acidic environment that draws minerals and collagen from the bones without affecting the final flavor. Bring slowly to a boil, then immediately reduce to the barest possible simmer — single bubbles breaking the surface every few seconds, no boil. Skim all grey foam that rises in the first 15 minutes. Simmer uncovered (or with lid cracked) for 12–18 hours.

Pour the broth through a fine-mesh strainer lined with a double layer of damp cheesecloth. Do not press the bones — gravity is the only force here. Discard the solids. Cool the broth to room temperature, then refrigerate overnight. The next morning, lift off and discard the solidified fat cap from the surface. The broth beneath should be solidly gelled, like brown aspic. Season lightly with salt only when ready to serve — salt concentrates as the broth reduces in subsequent cooking.