Endive Soup
(Alsace-Lorraine.) Trim and parboil 4 heads of chicory, drain it and chop it very fine. Add 2 ounces butter, salt, pepper, and mace, and 2 ounces flour. Then add 1 quart of veal stock and 1 cup of boiling milk. Cook for 1 hour, add yolks of 2 eggs, beaten in 1/2 cup of milk, and strain it through a sieve. Serve at once.
A classic French-style purée soup thickened twice — once with a butter-and-flour roux, once with an egg yolk liaison. The liaison is where it succeeds or curdles.
- The hinge: the yolksOnce the beaten yolks and milk go in, the soup must not boil or even approach a simmer — it will scramble into threads. Take the pan off the heat, temper the yolks with a ladle of hot soup, stir them back in, and hold below about 180F just long enough to thicken.
- Endive or chicory?The title says endive, the method says chicory, and at the time the two words were used interchangeably for several plants. Four heads points to Belgian endive (witloof) or curly endive/frisée rather than the loose chicory greens sold today; either works, but frisée and escarole are more bitter and want a longer parboil.
- Parboiling mattersFive to eight minutes in well-salted water, then a hard squeeze in the drained mass, removes the raw bitterness. Skipping it leaves the finished soup harsh under the milk and butter.
- MeasuresTwo ounces of butter is 4 tablespoons; 2 ounces of flour is a scant half cup, which makes a fairly stiff roux for a quart of stock. A quart is 4 cups, a cup 8 fl oz.
- MaceGround mace is the outer covering of the nutmeg seed, with a lighter, more floral note. A pinch is enough; nutmeg can stand in, used sparingly.
- Veal stockA light, unroasted veal stock was the standard neutral base of the period. A mild chicken stock is the closest supermarket equivalent; roasted beef or brown stock will overwhelm the endive.
- Cooking timeAn hour at a bare simmer is longer than the greens need but is what cooks the raw flour taste out of that heavy roux. Stir the bottom occasionally and keep the heat low, or the milk solids will catch and scorch.
- StrainingPushing it through a sieve at the end was the usual route to a smooth purée before blenders, alongside a tammy cloth or food mill. A blender or immersion blender first, then a sieve, gives a better texture with less work.
- YieldAbout five to six cups finished — four to six servings as a first course. It does not reheat well once the yolks are in, so make it to serve.
Alsace-Lorraine sat on the French-German border and had changed hands in living memory of this book's readers, which is part of why a cookery collection would flag a soup as coming from there at all. The dish itself is thoroughly French in construction: a vegetable purée bound with a roux and finished with a liaison of egg yolks, the technique Escoffier's generation codified. Endive and chicory were winter crops of northern France and Belgium — witloof chicory, forced in the dark to blanch it pale, is generally traced to Belgian growers in the mid-nineteenth century — and soups like this one were a way of making something delicate out of a bitter cold-weather green. The insistence on serving at once is not politeness; a yolk-bound soup will not survive being held.