Put the following ingredients into a stewpan: 

Some bits of bacon and lean ham, a carrot, all cut into dice, half an onion, a bunch of herbs, a few mushroom cuttings, four peppercorns and two cloves. 

To this add one and a quarter pint of good stock and a glass of Chablis, boil rapidly for ten minutes then simmer till it is reduced to a third. 

Pass through a sieve and use for masking meat, fowl, fish, etc.