Sole Mornay des Provençaux

Ingredients

Equipment Needed

• •12-inch (30 cm) ovenproof skillet
• •2-quart (1.9 litre) shallow gratin dish
• •Fine-mesh sieve
• •2-cup (480 ml) heatproof measuring jug
• •Flexible fish spatula
• •Parchment paper

Instructions

1. 1

   Prepare the service

   Heat the oven to 325°F (165°C) with a rack about 5 inches (13 cm) below the broiler element. Use 1 tablespoon of the measured butter to coat a 12-inch ovenproof skillet, a shallow gratin dish, and one side of a sheet of parchment cut to fit the skillet. Grate the Gruyère finely now; once the fish is poached, the work must move without a pause.

2. 2

   Poach the sole

   Season the fillets with most of the salt and half the white pepper. Fold each fillet in half with the former skin side inward, tucking the narrow tail underneath, then arrange them in one snug layer in the skillet. Add 1½ cups (360 ml / 360 g) of the fish fumet, reserving the rest cold, and dot the fish with 2 tablespoons of butter. Bring the liquid only to a tremble on the stovetop, cover buttered-side down with the parchment, and place the skillet in the oven for 5 to 8 minutes. Remove the fillets when they are opaque around the edges but faintly translucent at the thickest point, about 130 to 135°F (54 to 57°C); the glaze will finish them. Lift them carefully into the buttered gratin dish, arranging two fillets per serving and leaving them uncovered.

   A hard boil contracts the sole and squeezes out its moisture. Keep the fumet at the barest tremble; if it bubbles vigorously, pull the skillet off the heat before it goes into the oven.
3. 3

   Reduce the poaching liquor

   Pour the poaching liquor through a fine-mesh sieve into a heatproof jug, then return it to the skillet and add the white wine. Boil briskly until reduced to 1 cup (240 ml), about 8 to 12 minutes. Taste near the end: the reduction should be distinctly savoury but not salty. Pour it back into the jug and keep it hot.

4. 4

   Build the sauce vin blanc

   Switch the oven to high broil so the element is fully heated before glazing. In the emptied skillet, melt 2 tablespoons of butter over medium-low heat, stir in the flour, and cook the roux for 90 seconds without letting it colour. Whisk in the hot reduction by thirds, making each addition smooth before adding the next, then add the cream and simmer gently for 3 to 5 minutes. The sauce is ready when it coats the back of a spoon and a finger drawn through it leaves a clean path. Season with the remaining salt and white pepper, remove from the heat, and whisk in the final tablespoon of cold butter.

   If the sauce becomes lumpy, take it off the heat and whisk firmly, then pass it through the sieve if needed. If it tightens too far or shows greasy streaks after the final butter, whisk in the reserved cold fumet one teaspoon at a time. Ça se rattrape.
5. 5

   Nap and cover

   Tilt the gratin dish and spoon away any liquid released by the waiting fish; a wet base thins the sauce. Pour the hot sauce vin blanc evenly over the fillets, napping every exposed surface and letting a little pool between the portions. Shower the Gruyère liberally from edge to edge. The cheese stays on top, exactly as the source directs; it is not stirred into the sauce.

6. 6

   Glaze and serve

   Place the dish beneath the fully heated broiler and watch it continuously. Glaze for 1 to 3 minutes, rotating the dish once if needed, until the Gruyère has melted into a thin gold crust, darker at the high points, and the sauce bubbles around the rim. Check that the thickest portion of fish has reached at least 145°F (63°C) and flakes cleanly; if the cheese colours first, switch the oven back to 325°F (165°C) and give the fish another minute rather than burning the top. Bring the gratin dish directly to the table and serve at once. À table!

Chef Tips

• •Fumet is a concentrated fish essence, not a strong seafood broth. Choose a pale, unsalted fumet made from mild white-fish bones; salmon or shellfish stock takes over, while heavily salted shop stock becomes briny as it reduces.
• •Dover sole gives the finest, firmest texture. If it is unavailable, choose thin fillets from another mild flatfish and keep the same weight; the flavour and delicacy will change slightly, but the poaching and glazing method remains sound.
• •Grate the Gruyère finely and heat the broiler fully before the fish is sauced. Thick shreds or weak heat force the dish to linger while the cheese melts, and sole has no patience for that.
• •Serve the same dry white wine used in the sauce, provided it is good enough for the glass. Chablis or another restrained white Burgundy has the acidity to meet the cream without trampling the fish.

Advance Preparation

• •The fish fumet can be prepared up to 3 days ahead and refrigerated, or frozen for up to 3 months. Thaw it completely and taste for salt before reducing.
• •The Gruyère may be grated, the gratin dish buttered, and all sauce ingredients measured a day ahead. Keep the cheese covered and cold.
• •Do not poach or assemble the sole in advance. Begin the reduction as soon as the fish leaves the poaching pan and plan to serve within 20 minutes; this is a brief service sequence, not a holding dish.

Frequently Asked Questions

Nutrition Information

1 serving (about 320g)