Salt
Boil the vinegar, water, and salt and butter all together in a bright saucepan. Beat the yolks a little, add some of the boiling liquid and stir them together, then mix all and let come to the boiling point. It is on the same principal as making custard. If allowed to thoroughly boil it will curdle, and have to be thrown away; if taken off too soon it will not be rich and thick enough. One minute of stirring after the yolks are added is usually enough. Strain and set on ice to be cold for use.
The preceding will be found eminently satisfactory and can be used in almost every place that mayonaise would be employed. It can be made thicker or thinner as required, but when thinned must be rapidly beaten and the liquid--water or broth and vinegar--added by degrees, otherwise the dressing may separate and the butter come to the top. This, however, seldom occurs. It is generally an object to have mayonaise creamy white, for which purpose lemon juice is added to it, but the hollandaise dressing is golden yellow, and the better for vegetable salads like the following, which have no good looks of their own.
This is the method half of a cooked hollandaise dressing — a boiled egg-yolk sauce meant to stand in for mayonnaise on salads. The proportions belong to the entry above it in the book, so read it as technique rather than a standalone formula.
- Missing quantitiesThe text names vinegar, water, salt, butter and yolks but gives no amounts; the definite articles suggest they stood in an ingredient list above this passage, though the page itself does not say so. A workable ratio for this style is roughly 4 yolks to 1/4 cup vinegar, 1/4 cup water and 4 oz butter, but that is a reconstruction, not the author's measure.
- The hinge: heat, not timeIgnore "boiling point" as a literal target and work to 180-185F, when the yolks thicken and hold. Past about 190F the proteins tighten and the sauce breaks into curds and butterfat, which is exactly the failure the author describes.
- TemperingAdding a little hot liquid to the beaten yolks before combining is not optional. Poured the other way, the yolks set in threads before they can emulsify.
- A bright saucepanI.e. a clean, well-scoured pan; the book does not say what metal. Use stainless or enamelled steel; unlined aluminium reacts with vinegar and will grey the sauce.
- Strain and chillStraining catches any curd that has already formed and the chalazae from the yolks. This dressing is served cold, unlike a modern warm hollandaise, and it will set noticeably firmer in the refrigerator.
- Thinning it laterAdd water, broth or vinegar a spoonful at a time into a rapidly beaten sauce. Dumped in at once, the emulsion floods and the butter rises.
- KeepingA cooked yolk-and-butter dressing is still a perishable egg product. Refrigerate it covered and use within two days; do not leave it at room temperature through a long buffet.
- YieldFour yolks with the reconstructed liquid above give roughly a cup and a quarter, enough to dress salad for six to eight.
Hollandaise means simply "Dutch sauce," a name attached in French kitchens to butter-and-egg sauces sharpened with vinegar. What is notable here is that the author treats it as a rival to mayonnaise rather than a hot sauce for fish, and claims for it that it can be used "in almost every place that mayonaise would be employed." The comparison to custard is the working cook's shorthand -- the same coagulation, the same narrow window before curdling -- and the closing remark that the dressing suits vegetable salads "which have no good looks of their own" shows a period concern with how a salad looked as much as how it tasted.