Coquilles Saint-Jacques à la Parisienne — Scallops in Wine Sauce Gratin

Coquilles Saint-Jacques à la Parisienne is the classic French scallop preparation — the shells filled with sliced scallops, mushrooms, and a wine-enriched sauce, bordered with piped duchess potato, and gratinéed under the salamander. It is the dish that put scallops on the classical French menu and remains the benchmark for shell presentation. The preparation requires impeccable timing across multiple components. The scallops (6 large or 12 small, with corals if available) are poached gently in 200ml dry white wine and 100ml fish fumet with minced shallots for exactly 2-3 minutes at 75-80°C — overcooking is the mortal sin, as scallop protein toughens dramatically above 60°C internal temperature. Remove the scallops and slice into 5mm rounds. Reduce the poaching liquid by two-thirds. Build the sauce: add 200ml fish velouté to the reduced liquid, 80ml cream, reduce to nappant consistency, and finish with 20g butter and a squeeze of lemon. Fold in the sliced scallops, 100g mushrooms (sliced and cooked à blanc), and the corals (sliced). Pipe duchess potato (firm mashed potato enriched with egg yolk and butter) around the rim of clean scallop shells using a star nozzle. Fill the centre with the scallop mixture. Nap with additional sauce, sprinkle with fine Gruyère and breadcrumbs, and gratinée under the salamander at 280°C for 2-3 minutes until the potato is golden and the sauce bubbles. The dish must be served immediately — in the shell, on a plate with a folded napkin to prevent sliding.