Dutch Sauce
To one-half cupful of vinegar and two tablespoonfuls of consomme or strong stock, add one-half of a teaspoonful of freshly grated horseradish, one-half of a small onion, sliced, one-half of a teaspoonful of chopped parsley, onehalf of a teaspoonful of sugar, and one-half of a bay leaf. Cover and steep by the side of the fire for fifteen minutes. Strain, pressing out all of the liquids. Return to the saucepan with one teaspoonful of lemon juice and the slightly beaten yolks of three eggs. Place the saucepan over hot water on the side of the fire until the mixture thickens. Season to taste, with salt and cayenne,; stir in one tablespoonful of butter and serve with boiled or baked fish.
A vinegar-and-aromatic infusion finished with egg yolks — closer in structure to a béarnaise base than to the butter-heavy hollandaise most cooks expect from the name. Almost everything depends on heat control at the end.
- The hinge: never let the water boilThree yolks in a half cup of acidulated liquid will set somewhere around 160–170F and scramble by 180F. Keep the water in the lower pan hot but still, and pull the pan off the moment the sauce coats the back of a spoon.
- "By the side of the fire"On a range this means the coolest part of the hearth — a bare simmer, no bubbles. Use the lowest burner setting for the steeping stage and a bain-marie for the thickening stage.
- Vinegar strengthHousehold vinegars of the period were not standardized to today's 5 percent and varied in strength. Modern distilled white vinegar will make a sharp sauce; a white wine vinegar is likely to give a gentler result.
- Consomme or strong stockTwo tablespoons of a well-reduced, gelatinous stock, not canned broth. It is there for body as much as flavor, so a good homemade fish or veal stock is worth the trouble in a sauce this small.
- HorseradishFreshly grated root is far more volatile than the jarred product, which is already cut with vinegar. If using prepared horseradish, drain it and reduce the vinegar slightly.
- The butterOne tablespoon is all, which makes this thinner and more acidic than a hollandaise. Whisk it in off the heat so it emulsifies rather than melting into a slick.
- Yield and holdingAbout two-thirds of a cup, enough for roughly four servings of fish. Egg-thickened sauces hold poorly and do not reheat; make it while the fish rests and serve at once.
"Dutch sauce" is the English rendering of sauce hollandaise, and nineteenth-century British and American cookbooks used the two names loosely for any warm egg-and-butter sauce built on a vinegar reduction. What is notable here is the proportion: modern hollandaise is mostly butter, while this version leans on the infusion of vinegar, onion, bay and parsley — a method closer to the reduction that underlies béarnaise, and a reminder that the classic French sauce hierarchy was not yet fixed in household cookbooks.