Slaw Dressing
Beat yolks of 3 eggs with 1/2 cup sugar. 2 tablespoons melted butter. 1 teaspoon salt. 1 cup cream or milk. 1 teaspoon corn starch, dissolved in a little of the milk. 1 teaspoon mustard. 1/2 cup vinegar. A little cayenne pepper, and lastly the whites of eggs beaten stiff.
Cook in double boiler.
This is a boiled dressing rather than a mayonnaise: the eggs and starch, not oil, do the thickening. The original assumes you know what a cooked salad dressing should look like, so a few numbers help.
- The hinge: gentle heatCook over simmering, never boiling, water and stir constantly until the mixture coats a spoon, around 170-180F. Direct heat or a rolling boil will scramble the yolks and the dressing will break into curds that no amount of whisking recovers.
- Order of workWhisk the yolks, sugar, salt, mustard and cayenne together, stir in the cornstarch slurry, then the rest of the milk or cream, then the melted butter. Add the vinegar last of the liquids and add it slowly — dumping in half a cup of acid at once will curdle the dairy before the starch has set.
- The beaten whitesThe recipe adds them last and then cooks, so fold them into the thickened base over the water bath and keep stirring until they are cooked through. They lighten the dressing to something closer to a soft custard; overcook and the texture turns spongy and weepy.
- MustardHere this almost certainly means dry mustard powder rather than prepared jarred mustard, as in most cookery of the period. A teaspoon of powder is usually reckoned as roughly a tablespoon of prepared yellow mustard if that is all you have, though the flavor is sweeter and less sharp.
- Vinegar strengthCider vinegar sold for household use generally fell in the same 4 to 5 percent range as today, so the half cup can be treated as a straight swap, though home-made vinegar varied. It is a genuinely sharp dressing, balanced by the half cup of sugar -- taste before adjusting either.
- Cream or milkEither works, but whole milk gives a dressing thin enough to coat shredded cabbage without weighing it down, while cream produces something closer to a sauce.
- Yield and keepingMakes about two cups, enough for a large head of cabbage. It thickens further as it chills; loosen with a spoonful of milk. Refrigerate and use within three or four days.
Boiled dressings like this one were the everyday American salad sauce well before bottled mayonnaise reached most kitchens, and they suited cabbage in particular — a sweet-sour cooked custard clings to shredded slaw in a way that oil emulsions do not, and it uses dairy and vinegar rather than the expensive salad oil that many households bought sparingly. The name slaw comes through Dutch koolsla, cabbage salad, and by the time Mrs. Wilson was writing for the Philadelphia Public Ledger the dish was so standard that a cook book needed a dressing recipe more than it needed instructions for the cabbage. Wilson's version is notably sweet, half a cup of sugar to half a cup of vinegar, which reflects the period taste for a pronounced sweet-sour dressing on raw vegetables.