Filets de Soles Grand Duc

Filets de Soles Grand Duc (sole fillets with truffle, crayfish, asparagus, and glazed Mornay) teaches the discipline of composed fish cookery: every element is cooked separately, then brought together under one sauce without losing its own texture. The one true thing to know before touching a pan is this: the sole finishes twice, first in its poaching liquor and again beneath the glaze, so the poach must remain gentle and brief.

The original assumed a saucier on staff, fish fumet never far from the fire, mushroom liquor already waiting, and an overhead salamander fierce enough to color Mornay in moments. At home, make one quick mushroom liquor, hold a small Mornay base in a saucepan, and use a fully heated broiler over one oval platter. Cooked crayfish tails replace whole crayfish boiled and shelled to order, and a good preserved whole truffle may stand in when fresh is out of season. Those are changes of scale and equipment, not intent: eight folded fillets serve four, while the fumet poach, truffle, three crayfish tails between each fillet, Mornay glaze, and butter-bound asparagus all stay.

Making separate gallons of stock and sauce is brigade scaffolding, and it can go. Reducing the sole's poaching liquor into the Mornay is the dish, because it ties fish, mushroom, cheese, and cream into one flavor. The decisive step remains the poach: keep the liquor below a simmer and lift the sole while it is barely opaque, because the broiler finishes what the poacher begins.