Soup Verte
4 tablespoonfuls flour 3 tablespoonfuls Crisco 2 quarts stock 1 lb. spinach 1 bunch parsley 1 teaspoonful sugar 2 egg yolks 1 lemon Salt and pepper to taste Put stock into saucepan; add spinach and parsley, picked and thoroughly washed; let all boil twenty minutes; strain, rubbing puree through sieve. Return it all to saucepan, add Crisco and flour mixed together with cupful of water, sugar and strained juice of a quarter of lemon. Let boil five minutes. Beat yolks of eggs with 1/4 cupful water, add them gradually to soup off fire, and stir near fire until cooked. Soup must not boil after yolks are added. Season with salt and pepper and serve.
A green puree soup finished with an egg-yolk liaison. Two things decide whether it works: keeping the soup off the boil once the yolks go in, and not stewing the greens any longer than you must.
- The hinge: no boiling after the yolksOnce the tempered yolks are stirred in, hold the pan at a bare 160-175F, stirring, until the soup thickens slightly and coats the spoon. A boil will scramble the yolks and leave grainy flecks that no sieve will rescue.
- Temper the yolks properlyThe quarter cup of water helps, but ladle a cup of hot soup into the beaten yolks in a thin stream first, then return the mixture to the pan off the heat. Adding cold yolks straight to two quarts of hot soup is a gamble.
- CriscoCrisco is vegetable shortening, and this book exists to sell it. Butter is the better choice here for flavour; use 3 tablespoons of either. The fat and flour are mixed cold with a cup of water into a slurry rather than cooked as a roux, which is why it needs the full five minutes of boiling to lose its raw-flour taste.
- Twenty minutes of spinachA pound of spinach is cooked through in two or three minutes and turns olive-drab by twenty. For colour, simmer the parsley in the stock, add the spinach for the last three minutes, then puree. The long boil may have been aimed at extracting flavour into the stock, which good stock already supplies.
- Sieve or blender"Rubbing puree through sieve" is a blender or immersion blender now. Pass it through a fine sieve afterwards if you want the smooth texture the original was after; spinach stems leave threads.
- Quantities to watchA pound of spinach is a large amount by volume before cooking; expect to press it down into the stock. Only a quarter of the lemon's juice is used, added before the boil, so taste and adjust at the end rather than dumping the whole lemon in.
- YieldTwo quarts of stock plus the thickening and egg mixture gives roughly 8 to 10 cups, or six to eight first-course servings.
- Seasoning lastSalt after the liaison, not before, as the recipe itself directs. Stock carries salt of its own and this soup is easy to overshoot, so taste at the end.
"Soup verte" is kitchen-French for green soup, a member of the broad family of potages verts built on whatever leaf was cheapest and greenest -- spinach, sorrel, parsley, chard -- thickened with flour and finished with egg yolks in the old liaison manner. The egg-yolk finish is one of the oldest thickeners in European cookery and survives today mainly in sauces and in soups like Greek avgolemono; the lemon juice here does the same double duty of brightening the flavour and cutting the richness. What dates the recipe precisely is the Crisco: hydrogenated vegetable shortening was introduced by Procter & Gamble in 1911, and the company commissioned a run of recipe booklets and menu calendars in the following years to persuade cooks that it could stand in for butter and lard anywhere. A soup like this, where the fat is barely tasted, was a diplomatic place to start.