Sauce for Cold Fowl or Partridge

A pounded cold sauce in the old English manner: hard yolks carry the oil and vinegar into a loose emulsion, with anchovy and shallot doing the seasoning. It comes together in a few minutes and is best made an hour ahead.

• The spoon sizesA Victorian dessert-spoon holds roughly two teaspoons, about 10 ml. That gives around 4 teaspoons of oil to 6 of vinegar, far more vinegar than a mayonnaise. Expect a sharp, dressing-like sauce, and slacken it with more oil if you want it rounder.
• Pound before you mixThe final line is the hinge: the spice and aromatics, the cayenne and the shallot, are to be reduced to a paste before they go in. Add the shallot whole to the yolks and you get gritty flecks of raw shallot instead of a smooth sauce.
• The oil"Oil" in a receipt of this date most likely means salad oil, in practice olive. Use a mild olive or a neutral oil; a peppery modern extra-virgin will fight the anchovy.
• The anchovyOne anchovy of the period meant a whole salted fish, roughly equal to two modern tinned fillets. Rinse and blot the fillets before pounding, or the sauce turns very salty.
• The mustardAmbiguous as written. A teaspoon of English mustard powder is the likelier reading and gives real heat; a teaspoon of made mustard is milder and adds a little more liquid. Either works, but the powder needs a few minutes in the sauce to develop.
• EquipmentA mortar is still the best tool for this quantity, since a food processor bowl is too large to catch it. A small blender jug or a bowl and fork will do if you chop the shallot very fine first.
• Yield and servingMakes about 100 ml, enough for four helpings of cold chicken, partridge or pheasant. Rest it half an hour before serving and stir again; it separates on standing. Keep refrigerated and use within two days.