Take chicken bones or carcass, clean all meat off it. (Tip: you can freeze meat in a baggie for adding to soup later.)
(Optional: Some people like to roast the bones for an hour or so at this point, for a darker, richer-tasting stock. )
EITHER : Put bones / carcass in pot with enough water to cover. Bring to a boil, cover, and simmer for 45 minutes. OR Put in pressure cooker. Add enough water to cover bones. Cook for 30 minutes on high pressure (13 to 15 lbs for most North Americans. See Notes.) A couple bay leaves tossed into either process make an inspired addition.
Strain into a large bowl or tub; have a second go at picking more of the loosened meat off it, add that to your bag of frozen meat, and put the stock in fridge over night.
In the morning, scrape all the fat off the top; discard the fat.
Reheat the stock to boiling in microwave (or pot.) If you used a microwave, be careful of surge when removing.
Pour hot into half-litre (1 US pint) jars or 1 litre (US quart) jars.
Leave 3 cm (1 inch) headspace.
Put lids on, put in pressure canner.
Processing pressure: 10 lbs (69 kPa) weighted gauge, 11 lbs (76 kpa) dial gauge (adjust pressure for your altitude when over 300 metres / 1000 feet.)
Processing time: half-litre (1 US pint) jars for 20 minutes. OR 1 litre (1 US quart) jars for 25 minutes.