Jus rôti

"Roast gravy" should be exactly what it sets out to be - the juices recovered from roast meat or poultry. Crouillère-Chavot makes his from freshly roasted chicken. Season 10 chickens. Put three peeled cloves of garlic and a sprig of thyme inside each one. Brush with duck fat. Roast the chickens in a hot oven for about 50 minutes (depending on size), turning them and basting them often. This is critical to obtain a concentrated jus.

After roasting, remove the chickens, emptying any juices in the cavities on to the roasting tin or tins. Add 80ml water, 80ml veal stock and 160ml chicken stock to the tin. Scrape any sediment off the bottom. Leave the jus to settle for 30 minutes. Strain into a fresh container. Chill. Remove any fat which sets on the surface.

To flavour roast gravy with truffles: melt about a teaspoon of the fat from the roast in a pan. Add about 20g sliced fresh truffle. Warm through, but don't cook it. Add about 200ml of roast gravy. Heat, but don't boil. Adjust the seasoning. Taste and, if necessary, add a small squeeze of lemon juice. Set aside so the gravy can absorb the truffle aroma. Strain and reserve in sealed jars.