Périgueux Sauce

Sauce Périgueux (Périgord truffle sauce) teaches the discipline of reduction: the base must reach its density before the truffle enters, because truffle perfume will not survive a corrective boil. Keep that one truth at hand before touching the pan. Properly finished, the sauce falls from a spoon in a dark, glossy ribbon, carrying chopped black truffle through every serving.

The book assumed a saucier at a brisk fire, half-glaze already working, and a stockpot of very strong veal stock never off the fire. A home cook begins with the completed Madeira Sauce (No. 44), adds the prescribed half-volume of concentrated veal stock, and uses a wide heavy pan in place of brigade speed. The only modernization is the order of assembly and the home-scale batch: because the cross-referenced Madeira Sauce arrives as a finished component, the extra stock is reduced into it. The formula remains intact, one-sixth pint of truffle essence and three ounces of chopped truffle for every quart of Madeira sauce. One cook, one stove, one evening.

Straining is scaffolding, useful only if the stock leaves sediment; a fine-mesh sieve replaces the tammy. Reduction, the off-heat essence, and the chopped truffle are the dish, and they stay untouched. Reduce a little too far and the sauce can be loosened, ça se rattrape. Boil it after the truffle enters and its perfume is gone, so stop at a dense nappé before the finish.