Stock from a carcass
Put the bones of a roast chicken in a large pot with a halved onion, a carrot, a celery stalk, a bay leaf and a few peppercorns. Cover everything with cold water by about an inch, which is usually around three quarts. Bring it to a bare simmer, with a bubble breaking the surface every second or two, and skim off the gray foam that rises in the first 20 minutes. Simmer it uncovered for three to four hours, then strain it. Vegetable stock made from onion, carrot, celery and mushroom stems needs only 45 minutes.
Do not let it boil hard, because boiling churns the fat into the liquid and makes it cloudy and greasy. Do not salt it, because stock gets reduced later and the salt concentrates.
Cooling and keeping
A big pot of hot liquid cools slowly enough to be a food safety problem. Divide it into shallow containers, or set the pot in a sink of ice water and stir, so that it is in the refrigerator within two hours. Stock keeps three to four days chilled and several months frozen.
The pattern for any soup
- Cook a chopped onion, with carrot and celery if you have them, in two tablespoons of oil or butter with a pinch of salt over medium heat for eight to ten minutes, until soft but not brown.
- Add garlic, spices or a spoonful of tomato paste, and stir for one minute.
- Add the main ingredients and the liquid, using about one quart of stock for every pound to pound and a half of vegetables.
- Simmer for 20 to 30 minutes, until everything is tender.
- Add quick-cooking things last, such as small pasta, canned beans, leafy greens or cooked chicken, and give them five to ten minutes.
- Taste, then season with salt, pepper and a teaspoon of lemon juice or vinegar.
Blending and leftovers
For a smooth soup, a stick blender in the pot is the safest tool. If you use a countertop blender, fill it no more than halfway, take out the center cap of the lid, and hold a folded towel over the opening, because trapped steam can blow the lid off. Pasta and rice keep absorbing liquid overnight, so cook them separately if you plan on leftovers. Bring leftover soup to a boil when you reheat it.
Tip Keep a bag in the freezer for onion ends, carrot peels, celery tops and parsley stems. When it is full, you have the vegetables for a pot of stock.
