Duchess Soup
1 qt. milk 1 small onion 3 egg yolks 2 tablespoons butter 2 tablespoons Gold Medal flour 1 teaspoon salt Few grains pepper 2 tablespoons grated cheese Scald milk. Cook onion in butter until a golden brown, add Gold Medal flour and cook until frothy, blend with scalded milk and cook ten minutes. Rub through strainer and return to fire. Add cheese and seasonings. Beat yolks until light, dilute with 1/2 cup of soup, put in tureen and pour hot soup slowly over this, stirring briskly.
A plain veloute-style milk soup finished with an egg-yolk liaison. The only difficult moment is the last one, and everything before it is straightforward.
- The hinge: the liaisonThe yolks are thinned with a half cup of hot soup, then the rest is poured over them off the heat, in the tureen. Do not return the soup to the stove afterward or the yolks will scramble and the texture goes grainy.
- Scalding milkScalded means heated to about 180F, when a ring of small bubbles forms at the edge and the surface steams. It is not a boil, and boiling the milk here will only give you a skin to strain out.
- Cook the roux properly"Cook until frothy" describes the stage at which the butter-and-flour paste bubbles up; a minute or two at this stage is generally taken to cook off the raw flour taste. The browned onion is cooked in the same butter, so this roux will be blond rather than white, which is intended.
- Straining"Rub through strainer" means pressing the softened onion through a fine sieve with the back of a ladle, not simply pouring the soup through. That pulp is most of the flavor. A brief blitz with an immersion blender before sieving makes it easier.
- The cheese"Grated cheese" is unqualified here; in early twentieth-century American books it could cover Parmesan or a firm domestic cheese, and the choice is left to the cook. Add it off direct heat and stir until melted; a full boil after the cheese goes in will make it stringy.
- SeasoningA teaspoon of salt for a quart is a reasonable starting point, but the cheese carries salt of its own. Season after the cheese has melted, not before.
- YieldA quart of milk plus enrichment gives four generous cups, so four first-course servings. It thickens noticeably as it stands and does not reheat well once the yolks are in.
"Duchess" (a la duchesse) was one of the stock garnish-and-style names of nineteenth-century French cookery that American cookbooks borrowed wholesale; it attached itself to potato mixtures bound with egg yolk, to small pastry cases, and, as here, to pale cream soups enriched with yolks. The name is generally taken to signal richness and a light color rather than any specific origin, and its use varied considerably from book to book. Its appearance in a milling company's cookbook is no accident: the whole point of a soup like this, from Washburn-Crosby's perspective, is the two tablespoons of flour in the roux. Branded flour cookbooks were given away or sold cheaply through the early twentieth century to demonstrate that a sack of patent flour was good for far more than bread, and thickened cream soups, then a fixture of the genteel first course, made the argument neatly.