Herring Sauce
Chop a few herring fine, add to it some soup stock, a spoonful of flour browned in hot fat, also an onion chopped very fine. (The herring should be washed in cold water before adding to the stock.) Place on the fire to boil a few minutes, then add a little vinegar and sugar; strain the sauce through a fine sieve and add a few capers and one wineglass of white wine. When it comes to a boil, thicken with the yolk of two eggs.
A brown-roux sauce built on salt herring, meant for boiled beef, tongue or potatoes. Two things in the original need attention: the herring is not fresh fish, and the egg-yolk finish cannot be boiled.
- The herring is salt herringThe herring is almost certainly cured, not fresh -- the direction to wash it in cold water points to barrel-cured salt herring, the form most often meant when a recipe of this period says simply "herring." A cold-water rinse alone will not fix a heavily salted fish; soak it several hours, changing the water, and taste before it goes in. If you substitute pickled or marinated herring from a jar, drain it and cut back the vinegar, since it is already acidulated.
- Never boil after the yolks go inThe instruction to thicken "when it comes to a boil" will scramble the eggs. Beat the yolks with a few spoonfuls of the hot sauce to temper them, stir the mixture back off the heat, and hold the pan below 180F until it coats a spoon.
- A wineglassIn these books a wineglass is about 2 fl oz, roughly a quarter cup. Any dry white will do; the sauce is assertive enough that nothing delicate is wasted on it.
- "A spoonful of flour browned in hot fat"This is a brown roux, about a tablespoon of flour to a tablespoon of fat. Cook it to the color of an old penny before the stock goes in, otherwise the sauce tastes of raw flour and never develops the nutty background the recipe assumes.
- Quantities are left to youNo volume of stock is given, and the fish is only "a few herring." Roughly two cups of stock to a couple of soaked herring gives a pourable sauce; reduce or add stock to reach the consistency you want before the yolks go in, since you cannot boil it down afterward.
- Vinegar and sugarStart with a teaspoon of each and adjust. This is a sweet-sour seasoning, and the balance depends entirely on how salty the herring finished up.
- Straining, then capersThe order matters: the sauce is sieved to catch bones and onion, and the capers go in afterward so they stay whole. Chop them or leave them, but add them at the end.
- YieldAt the quantities suggested above, roughly two cups, enough for six servings alongside boiled meat or potatoes. It does not reheat well once thickened with yolks.
Herring sauces of this type belong to the northern European repertoire that came to American cookbooks through German and German-Jewish households, where cured herring was a year-round staple long before refrigeration made fresh fish ordinary. The sweet-sour seasoning, the brown roux, the capers and the egg-yolk liaison all point to the same family of dishes as the sauces served with boiled beef and tongue in nineteenth-century German cooking. The recipe's silence on quantities is characteristic of the period: a cook who kept cured herring on hand did not need to be told how much to use, and books like this one assumed a reader who could judge thickness and seasoning by eye.