MAKES ABOUT 3.5 LITRES
2.7kg beef bones or more if you have them, preferably with some scraps of meat on them, cut into small pieces
2 large onions, quartered
2 large carrots, quartered
2 celery stalks, cut into chunks
large bouquet garni, including parsley stalks, bay leaf, sprigs of thyme and a sprig of tarragon
Add enough water to cover the bones, about 4 litres. Bring slowly to the boil. Simmer gently for 5-6 hours, topping up with water if necessary. Strain, leave it to cool, and skim off all the fat before use.