Cucumber Soup
3 large cucumbers 2 tablespoons butter 3 tablespoons flour 3 cups White Stock III 1 cup milk 1 slice onion 2 blades mace 1/2 cup cream Yolks 2 eggs Salt and pepper Peel cucumbers, slice, and remove seeds. Cook in butter ten minutes; then add flour and stock. Scald milk with onion and mace. Combine mixtures and rub through a sieve. Reheat to boiling-point and add cream and egg yolks. Season with salt and pepper.
A classic velouté-style purée soup: cucumber softened in butter, bound with a roux and stock, finished with cream and egg yolks. The finishing is where it succeeds or curdles.
- Do not boil after the yolks go inBring the sieved soup to boiling point before the liaison, then take it off the heat. Whisk a ladleful of the hot soup into the cream and yolks first, return the mixture to the pan, and hold it below a simmer (about 180F) until it thickens slightly. Boiling will scramble the yolks into grains no sieve will fix.
- White Stock IIIA cross-reference to another entry in the same book, presumably a light veal or chicken stock. Any light, low-salt chicken stock works; avoid anything dark, heavily herbed or already salted, since the soup is finished with salt at the end.
- Blades of maceMace is the lacy outer covering of the nutmeg, sold whole as flattened "blades." Conversions vary, but two blades is somewhere in the region of a quarter to a half teaspoon of ground mace; ground mace cannot be strained out — infuse it in the milk and accept a faint speckling, or substitute a light grating of nutmeg added at the end.
- CucumbersThree large field cucumbers give roughly 4 to 5 cups sliced after peeling and seeding. Modern long English cucumbers have negligible seeds and thin skin; if the purée runs thin, a pinch more flour or a few minutes' extra cooking compensates.
- SievingThe original assumes a hand-worked sieve. A blender or immersion blender does the work in seconds, though passing the purée through a fine strainer afterwards still catches skin and seed fragments and gives the smooth texture the recipe intends.
- Cooking the cucumberTen minutes in butter should soften without browning — keep the heat low and the pan covered. Any colour on the butter or the flour will tint the finished soup, which is meant to be pale green-white.
- YieldAbout 5 cups, serving four as a first course. It does not reheat well once the liaison is in; warm gently over low heat and never let it bubble.