Ingredients:

Chicken bones (about 1kg)
1 large onion, quartered (no need to peel)
2 carrots, roughly chopped
2 celery stalks, roughly chopped
4 garlic cloves, smashed (no need to peel)
2 bay leaves
A small bunch of fresh thyme (or 1 tsp dried thyme)
10 peppercorns
2 tablespoons apple cider vinegar (helps extract nutrients from the bones)
8-10 cups of water (enough to cover everything in the pot)

Instructions:

Prep the Bones: Roast the bones in the oven at 400°F (205°C) for 20-30 minutes for added flavor.

Combine Ingredients: Place the bones in a large pot or a slow cooker. Add onions, carrots, celery, garlic, bay leaves, thyme, peppercorns, and apple cider vinegar. Cover with water.

Simmer Gently: Bring to a gentle boil, then reduce the heat to a simmer. For a pot, simmer for 4-6 hours; for a slow cooker, set on low for 12-24 hours. The longer it simmers, the richer and more flavorful it will be.

Strain: Carefully strain the broth through a fine mesh strainer or cheesecloth to remove the solids. Discard the solids.

Cool and Store: Let the broth cool, then store it in the refrigerator or freezer. In the fridge, it will keep for up to 5 days; in the freezer, for up to 3 months.

Skim Fat: Once cooled in the fridge, skim off any solidified fat from the top if desired.