Chicken stock

Another way I use leftovers from a whole roast chicken is to make chicken stock. I loosely follow Ina Garten's method. Some of my modifications:

-- I often cut the recipe in half.
-- Instead of whole, raw chickens, I use the leftover carcass (ugh, isn't there a more appetizing word?) from my roasted meal
-- Whenever I have vegetable odds & ends (asparagus spears, extra onions, zucchini, squash, etc), I keep adding them to a large freezer bag for use in this stock.
-- I've substituted dried herbs for fresh in a pinch.

3 (5-pound) roasting chickens
3 large yellow onions, unpeeled and quartered
6 carrots, unpeeled and halved
4 stalks celery with leaves, cut into thirds
4 parsnips, unpeeled and cut in half, optional
20 sprigs fresh parsley
15 sprigs fresh thyme
20 sprigs fresh dill
1 head garlic, unpeeled and cut in 1/2 crosswise
2 Tbsp. kosher salt
2 tsp. whole black peppercorns

Place the chickens, onions, carrots, celery, parsnips, parsley, thyme, dill, garlic, and seasonings in a 16 to 20-quart stockpot. Add 7 quarts of water and bring to a boil. Simmer, uncovered, for 4 hours. Strain the entire contents of the pot through a colander and discard the solids. Chill the stock overnight. The next day, remove the surface fat. Use immediately or pack in containers and freeze for up to 3 months.