Purée de Flageolets, otherwise Musard

Purée de Flageolets, dite Musard (silken flageolet soup), teaches one severe little truth: a bean purée can only be as smooth as the bean is tender. Let the flageolets cook past salad tenderness, until one collapses under the tongue; then their starch gives body without roux, and the passed soup settles in the bowl with a pale green gloss.

The original kitchen assumed a cook watching the soup pot, white consommé never off the fire, a mortar for pounding, a tammy for passing, and enough hands to boil milk while someone else skimmed. This two-quart translation gives one cook a food processor in place of the mortar, a fine-mesh sieve in place of the tammy, and good unsalted pale chicken stock when finished consommé isn't waiting. Those tools and brigade hands are scaffolding. The gentle cooking, true passing, boiled milk, and final butter are the dish, so they stay. One cook, one stove, one evening.

Fresh flageolets, used at twice the dry volume just as the source directs, make the sweeter, greener bowl; dried beans make the sound pantry version. Before you touch the pan, remember the point that cannot be bargained away: cook the beans completely before you pass them. Grit cannot be sieved into silk.