2-3 each chicken backs, wings and necks
2 carrots, peeled and chopped
1 yellow onion, peeled, chopped
2 celery stalks, chopped
1 leek, halved, washed, chopped
1 bay leaf
Bring a pot of water and the bones to a boil, reduce to a simmer. Remove all the foamy scum that comes to the surface of the pot with a ladle. Add the vegetables and simmer for 3 hours, making sure you remove the scum every 30 minutes or so.
Strain, reduce at a simmer for about 30-45 minutes. Clean the scum off the top. Cool the stock to room temperature before refrigerating or freezing.