Cambridge sauce

Cambridge sauce is an English sauce for cold meats. Larousse (1961) indicates that it is made by pounding together hard-boiled egg yolks, anchovy filets, capers, chives, chervil, and tarragon, adding English mustard, and beating in oil and vinegar "in the same way as for mayonnaise". The resulting sauce is rubbed through a fine sieve or cloth, and finished with chopped parsley and a pinch of cayenne.