Purée de Navets, otherwise Freneuse

Purée de Navets, otherwise Freneuse (silken turnip soup), teaches one true thing before you touch the pan: turnips must soften completely without taking colour. The measured sugar isn't there to make a sweet soup. It quiets the turnip's peppery edge so butter, consommé, and milk can reveal its gentler character.

The classical formula assumed white consommé never off the fire, a saucier free to mind turnips and potatoes in separate pans, and a tammy with practiced hands to force the purée through. This home batch keeps the book's one-pound turnip ratio and separate cooking sequence, replaces the tammy with a food mill and fine sieve, and finishes at about two quarts. The dedicated brigade hand is scaffolding and can go; the parboiling, butter stewing, sugar, potato binding, and hot-milk finish are the dish and must stay. One cook, one stove, one evening.

Freneuse should arrive ivory-gold and perfectly smooth, with enough body to leave a broad wake behind the ladle. Butter-fried croûtons give each spoonful its crisp edge. Watch the turnips while they étuver gently in butter, because preventing browning is the step that decides the whole pot.