Mousseline Alexandra

Ingredients

Equipment Needed

• •Food processor with metal blade
• •Fine-mesh sieve
• •Instant-read thermometer
• •3-quart ovenproof sauté pan with tight-fitting lid
• •Two large serving spoons for shaping
• •Slotted fish slice
• •Broiler-safe oval serving platter

Instructions

1. 1

   Chill and cut

   Put the food-processor bowl, blade, and a metal mixing bowl in the freezer for 15 minutes. Butter a 3-quart ovenproof sauté pan with 1 tablespoon (15 ml / 14 g) of the butter. Cut 8 very thin rounds from the reserved salmon, about 1½ inches (4 cm) across, then dice the trimmings and combine them with the remaining diced fish. Return the salmon, caps, egg whites, and cream to the refrigerator. Cold isn't a nicety here. It keeps the fish protein and cream joined in a stable emulsion.

2. 2

   Make the mousseline

   Put the diced salmon in the chilled processor with 1 teaspoon (5 ml / 6 g) of the salt and ¼ teaspoon (1.25 ml / 0.5 g) of the white pepper. Pulse until the fish becomes smooth and tacky, scraping the bowl once. Add the egg whites and process just until absorbed. With the machine pulsing, add ¾ cup (180 ml / 180 g) of the cream in four additions, waiting for each addition to disappear before adding the next. The farce mousseline should look satin-smooth, mound softly on a spoon, and remain quite cold.

   Poach a teaspoon of the farce in barely trembling water for 2 minutes. If it is firm or rubbery, pulse in more cream 1 tablespoon at a time, up to the full cup, and test again. If it spreads or weeps fat, stop. Ça se rattrape: set the bowl over ice for 10 minutes, then process briefly until the emulsion tightens. Warmth, not a lack of flour, is usually the culprit.
3. 3

   Build the Mornay

   Melt 2 tablespoons (30 ml / 28 g) of the butter in a saucepan over medium-low heat. Stir in the flour and cook the roux for 2 minutes without letting it color. Add the milk a little at a time, whisking the first additions into a smooth paste before thinning it with the rest. Simmer gently for 6 to 8 minutes, stirring into the corners, until the béchamel coats the back of a spoon. Take it off the heat and whisk in the Gruyère and Parmesan until smooth. Season with some of the remaining salt and white pepper. Cover directly at the surface and keep warm.

   If the béchamel forms lumps, pass it through a fine sieve. If the cheese turns oily, the heat was too fierce; take the pan off the stove and whisk in 1 tablespoon of cold milk. The Mornay should flow in a thick ribbon, not sit like paste.
4. 4

   Mold and cap

   Heat the oven to 325°F (165°C). Dip two large spoons in cold water. Scoop a generous spoonful of mousseline with one and pass it between the spoons two or three times to form a smooth oval. Set it in the buttered sauté pan and repeat to make 8 quenelles, leaving a little room between them. Lay one thin salmon round flat on each quenelle. Pour the hot water carefully down the side of the pan until it comes about one-third of the way up the quenelles, then cover tightly.

5. 5

   Poach very gently

   Set the covered pan in the oven and poach for 14 to 18 minutes. The liquid should barely quiver, never boil, and the quenelles are ready when they feel resilient under a fingertip and register 145°F (63°C) at the center. If the water begins bubbling, remove the pan, add a small splash of cold water, lower the oven by 25°F (15°C), and continue gently. Hard boiling makes a fine mousseline coarse, but catching it early saves it.

6. 6

   Drain and arrange

   Lift the quenelles carefully with a slotted fish slice and drain them for a moment on a clean lint-free kitchen towel, the honest home equivalent of the linen in the original method. Arrange them salmon-side up in a ring on a broiler-safe oval serving dish. Place one thin truffle slice on each salmon cap. Rewarm the Mornay over low heat; if it has tightened, loosen it with milk 1 tablespoon at a time until it again falls in a heavy ribbon.

7. 7

   Butter the peas

   Cook the peas with 2 tablespoons (30 ml / 30 g) of the poaching water and a pinch of salt in a covered saucepan until just tender, 3 to 5 minutes depending on whether they are fresh or frozen. Uncover and let every trace of water evaporate. Fold in the remaining 2 tablespoons (30 ml / 28 g) of butter until the peas are glossy and lightly bound together. Cover and take them off the heat.

8. 8

   Coat and glaze

   Set the broiler to high. Spoon the warm Mornay over every quenelle, coating them completely without flooding the platter. Place the dish about 4 inches (10 cm) below the broiler and watch without stepping away, 1 to 3 minutes, until the sauce swells slightly and freckles deep gold. The broiler is your salamander, and it works quickly. Spoon the buttered peas into the center of the ring and carry the whole dish to the table at once. À table!

Chef Tips

• •Choose a thick center-cut salmon fillet and remove every pin bone. Wild salmon is leaner and may take less cream, so trust the test quenelle and stop adding cream once the texture is tender.
• •A good whole preserved black truffle is the classical pantry's honest answer when fresh truffle isn't in season. Drain and dry it well. Truffle oil is not an equivalent; it perfumes the whole dish and erases the salmon.
• •Asparagus tips may replace the peas exactly as the source allows. Use 10½ ounces (300 g), blanch until just tender, drain thoroughly, and bind them with the same 2 tablespoons (30 ml / 28 g) of butter.
• •Mousselines are individual portions of forcemeat, not one large mold. Two quenelles per guest preserve the original circular presentation while making the dish generous enough for a main course.
• •Serve with dry Champagne or a restrained white Burgundy. The wine needs enough acidity to meet the Mornay and enough composure not to trample the truffle.

Advance Preparation

• •The salmon mousseline can be prepared up to 4 hours ahead. Press food-safe wrap directly against its surface and keep it below 40°F (4°C); shape only when the poaching pan and oven are ready.
• •The Mornay can be made one day ahead. Cover directly at the surface, refrigerate, then reheat over the gentlest heat with a few spoonfuls of milk until it flows in a thick ribbon.
• •The salmon caps and truffle slices can be cut earlier in the day and kept separately covered in the refrigerator. Finish the peas and glaze the quenelles only when the table is ready.

Frequently Asked Questions

Nutrition Information

1 serving (about 375g)