Merlan sur le Plat

Ingredients

Equipment Needed

• •Two shallow ovenproof plat or gratin dishes, about 12 x 8 inches (30 x 20 cm) each
• •Narrow flexible filleting knife
• •Long-handled basting spoon
• •Wide 10-inch (25 cm) sauté pan for finishing the reduction
• •Instant-read thermometer
• •Flexible fish spatula

Instructions

1. 1

   Prepare liquor and oven

   If the mushroom cooking liquor isn't already prepared, combine the sliced button mushrooms and cold water in a covered saucepan. Bring them to a bare simmer, cook gently for 10 minutes, then strain without pressing, which would cloud the pale liquor. Measure 2 cups, topping up with water if necessary, and keep it hot; reserve the cooked mushrooms for another meal. Heat the oven to 475°F (245°C). Spread 3 tablespoons of the softened butter generously over two shallow ovenproof dishes.

2. 2

   Prepare the whiting

   Pat each whiting thoroughly dry, including the cavity, and season with the fine sea salt. Following the method of Sole sur le Plat (No. 837), lay a fish on its side and slide a narrow flexible knife between the exposed upper fillet and the ribs, working from the dorsal edge toward the backbone. Loosen the flesh only partway, leaving it attached along the outer edge, head, and tail. Slip 1 tablespoon of butter into the pocket against the bones, then repeat with the remaining fish. Arrange two whiting head-to-tail in each buttered dish, loosened sides facing up.

   Keep the blade nearly flat against the bones. If the skin begins to stretch or tear, stop cutting; the pocket needs room for butter, not the proportions of a detached fillet.
3. 3

   Moisten and bake

   Divide the hot mushroom cooking liquor between the dishes, about 1 cup per dish, and sprinkle the lemon juice over the fish. The liquor should surround the whiting in a shallow layer without covering it. For the wine variation, use the white or red wine instead of the mushroom liquor, first stirring the melted pale meat glaze into the wine; do not use both liquids. Set the dishes on the upper-middle oven rack and bake for 4 minutes before beginning to baste.

4. 4

   Baste to a glaze

   Open the oven and spoon the bubbling liquor over the fish, directing some into each butter pocket. Repeat every 2 to 3 minutes. Begin checking the whiting after 12 minutes: it is done when the flesh beside the backbone has turned opaque, releases cleanly when nudged, and reaches 145°F (63°C) at its thickest point. The liquor should reduce at the same time into small, glossy bubbles that cling to the spoon. If it thickens before the fish is ready, add a tablespoon of hot water and lower the oven to 450°F (230°C).

   Basting is not ceremony. Each spoonful coats the lean whiting with butter while exposing more liquor to the oven's heat, so cooking and reduction arrive together.
5. 5

   Rescue the timing

   If the whiting is cooked before the liquor becomes syrupy, lift the fish carefully onto a warm tray. Pour the liquor into a wide sauté pan and boil it briskly until it coats the back of a spoon in a thin, translucent film, then return it to the baking dishes. This replaces the brigade's fierce finishing heat without sacrificing the fish. If the glaze turns oily instead of glossy, remove it from the heat and whisk in 1 teaspoon of cool water. Ça se rattrape. If it becomes sticky, loosen it with hot water a teaspoon at a time.

6. 6

   Coat and serve

   Return the whiting to their dishes if they were lifted out, then spoon the reduced liquor repeatedly over each fish until the skin wears a translucent, butter-gold coat. The glaze should flow slowly, not sit like paste, and only a shallow spoonful should remain around the fish. Carry the dishes straight to the table and serve the whiting from the vessels in which they cooked. À table!

Chef Tips

• •Choose small whole whiting with clear eyes, bright silver skin, red gills, and flesh that springs back under a finger. Ask the fishmonger to scale, gut, and trim them, but keep the fish whole; the bones protect this delicate flesh and give the liquor body.
• •Mushroom cooking liquor should be pale, clean, and gently earthy, not a dark roasted mushroom broth. Cook plain white button mushrooms without browning, strain the liquor, and save the mushrooms for an omelette or another supper.
• •For Merlan sur le Plat au vin rouge or au Chablis, replace the mushroom cooking liquor measure-for-measure with wine and add the pale meat glaze named in the source. A brigade drew that glaze from its stockpot; at home, use true unsalted veal or chicken demi-glace if pale meat glaze isn't waiting in your kitchen. Bouillon concentrate is too salty for a liquid reduced this far.
• •Serve at once, with boiled potatoes or plain rice ready to catch the glaze. A dry Chablis suits the mushroom version, while the red-wine variation wants a light, supple red served cool.

Advance Preparation

• •The mushroom cooking liquor can be prepared up to 2 days ahead, chilled promptly, and kept covered in the refrigerator. Reheat it to a simmer before adding it to the fish.
• •The whiting can be cleaned, dried, and partially loosened from the bones up to 6 hours ahead. Refrigerate uncovered on a tray, then add the salt and butter only when the oven is hot.
• •Do not bake the dish ahead. Whiting is lean and delicate, and reheating steals the tenderness that the basting worked to protect.

Frequently Asked Questions

Nutrition Information

1 serving (about 225g)