Sauce Piquante.
Pound a table-spoonful of capers and one pound of minced parsley as fine as possible, add the yolks of three hard eggs; rub them together with a table-spoonful of mustard. Bone six anchovies, pound them, and rub them through a hair sieve; mix with these two spoonfuls of oil, one of vinegar, one of shalot, and a few grains of cayenne pepper. Rub all together in a mortar till thoroughly incorporated; then stir them into half a pound of good gravy, or melted butter, and pass the whole through a sieve.