Roasted Duck Breasts with Wild Mushroom Stuffing and Red Wine Sauce

Step 1

Make the stuffing: Preheat the oven to 350°F. Bake the bread cubes in a single layer on a rimmed baking sheet until just golden, about 25 minutes. Let cool completely. Pulse in a food processor (in batches, if needed) until coarse crumbs form, about 15 seconds; transfer to a bowl. Add 1/4 cup oil; toss well. Spread the bread crumb mixture on the baking sheet, and bake, stirring occasionally, until deep golden brown, about 15 minutes. Transfer to a large mixing bowl.

Step 2

Heat the remaining 3 tablespoons oil and 2 tablespoons butter in a large skillet over medium-low heat until the butter has melted. Add the leeks, celery root, and garlic; cook, stirring occasionally, until the leeks are soft, about 15 minutes. Raise heat to medium. Stir in the mushrooms and thyme; season with salt and pepper. Cook, stirring occasionally, until the mushrooms are soft, about 10 minutes. Remove from heat. Stir the vegetable mixture into the bread crumb mixture; let cool completely.

Step 3

Prepare the duck: Place the duck breasts, skin sides up, on a cutting board. Using a sharp knife, score lines, 1/2 inch apart, in a cross-hatch pattern into the fat; cut almost all the way through, but do not cut into the flesh. Season both sides with salt and pepper. Cut 6 14-inch pieces of kitchen twine. Lay 3 pieces of twine about 2 inches apart on a cutting board. Place 1 duck breast half, skin side down, crosswise over the twine. Place about 1/2 cup stuffing on top of the duck. Top with another breast half, skin side up. Tie together tightly with the twine. Repeat with the remaining breasts. Stuffed duck can be refrigerated, covered, overnight. Bring to room temperature before cooking.

Step 4

Bake the remaining stuffing: Preheat the oven to 375°F. Butter an 8-inch-square baking dish; set aside. Stir together the remaining stuffing and 1 1/4 cups stock in a large bowl. Transfer to the prepared dish. Bake until the top is crisp and pale golden brown but the center is still moist, about 30 minutes.

Step 5

Meanwhile, cook the duck: Heat a large skillet over medium heat. Add the duck breasts to the skillet. Cook, turning once, until golden brown, 5 to 7 minutes per side. Transfer the breasts to a plate; pour the fat from the skillet into a heatproof container. Return the breasts to the skillet, and place it in the oven. Cook until an instant-read thermometer inserted into the thickest part of the meat registers 125°F for rare, 25 to 30 minutes. Transfer to a plate; let rest in a warm place, loosely covered with foil, 15 minutes. Pour the fat from the skillet.

Step 6

Make the sauce: Lightly wipe out the skillet, and place it over medium-high heat. Add the wine; cook until reduced by half, about 5 minutes. Add the port, if desired, and the stock. Simmer until reduced by half, about 5 minutes. Add the accumulated juices from the duck to the skillet. Season with salt and pepper; whisk in the butter. Pour the sauce through a fine sieve into a gravy boat. To serve, slice the duck, and drizzle with sauce, with baked stuffing on the side.