1 roasted chicken carcasses (wingtips are desirable)
Ice, approximately 1 pound (optional, cold water will work as well)
1 large yellow onion, diced
2 small carrots, diced
1 small head of fennel, diced
Small bouquet of thyme, parsley, fresh bay (optional)
Assemble your ingredients.
Transfer the carcasses to a stock pot large enough to accommodate the bones with plenty of headroom.
Cover the bones with a generous amount of ice (This step is optional and will yield a more clear broth. If you don't have ice, just use cold water). They should be completely covered. If possible work the ice down into the stock pot and between the bones so that the ice is evenly distributed throughout the pot.
Cover the bones with the water. The bones should be completely submerged, add more water if necessary. You want the water to go from as cold as possible to the final cooking temperature over an extended period of time. This will slowly extract flavor and nutrients from the bones and ensure a flavorful, nutritious and crystal clear broth.
Place the stock over a medium burner and slowly bring the contents up to 170-190 degrees. Once the temperature is within that range, turn the burner down to its lowest setting. Maintain this temperature, which should look like a very light simmer, for about two hours.
While cooking the stock, skim off any foam that rises to the surface every 30 minutes or so. This is the proteins coagulating and rising to the surface. If you were to boil your broth these coagulants and any remaining fat will cloud your broth, capture many of the nutrients in your stock, and basically leave you with a cloudy, bone flavored, unappetizing meat water.
When you are satisfied that you have skimmed off all of the “impurities”, pitch in your aromatics. That is, add your onion, carrot, fennel, and if you choose add the bouquet of herbs.
Simmer for an additional 30-45 minutes.
Strain your broth through a conical sieve or basic kitchen strainer. If you want a clearer broth, strain the broth a second time through a cheesecloth lined strainer.
Chill immediately or chill to below room temperature and/or proceed to processing for canning. The broth will keep for up to 5 days refrigerated or up to two months frozen.