Pork Loin Roast with Caramelized Onions and White Wine–Dijon Sauce

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Ingredients

  • 1 /2 cup Dijon mustard
  • 1 /4 cup whole-grain mustard
  • 1 /4 cup dry sherry
  • 6 tablespoons unsalted butter (3 ounces), softened, divided
  • 1 teaspoon fresh thyme leaves
  • 1 teaspoon cayenne pepper
  • 5 1/2 teaspoons kosher salt, divided
  • 1 (4-pound) boneless pork loin roast
  • 1 /4 cup canola oil, divided
  • 2 medium-size red onions, cut into 
8 wedges each
  • 1 pound cipollini onions, peeled
  • 6 large shallots (about 9 ounces), peeled and halved lengthwise
  • 3 /4 teaspoon black pepper, divided
  • 1 /4 cup dry white wine
  • 2 tablespoons dark brown sugar
  • 4 thyme sprigs, plus more for serving
  • 1 /2 cup water

Preparation

Step 1

Whisk together Dijon, whole-grain mustard, sherry, 2 tablespoons butter, thyme leaves, cayenne, and 1 teaspoon salt in a large bowl until combined. Add pork loin to bowl, turning to coat. Cover and chill at least 4 hours or up to overnight.

Preheat oven to 350°F. Remove pork loin from marinade, reserving 3 tablespoons marinade. Discard remaining marinade. Season pork on all sides with 2 teaspoons salt.

Heat 2 tablespoons oil in a large skillet over high. Add pork, and cook until browned on all sides, about 4 minutes per side. Remove from skillet, and set aside. Toss together red onions, cipollini onions, shallots, 2 teaspoons salt, 1/2 teaspoon black pepper, and remaining 2 tablespoons oil. Add half of onion mixture to skillet, and cook, without stirring, until browned on one side, about 2 minutes. Remove onion mixture from skillet, and place in bottom of a heavy-duty metal roasting pan. Repeat with remaining half of onion mixture.

Place a roasting rack over onions in roasting pan, and place browned pork on rack. Bake in middle of preheated oven until a meat thermometer inserted into center of pork registers 130°F, about 1 hour. Remove pork from pan, and transfer to a cutting board. Let rest 20 minutes before slicing. Using a slotted spoon, transfer onions to a plate.

While pork rests, place roasting pan on stovetop. Add wine, brown sugar, thyme sprigs, reserved 3 tablespoons marinade, remaining 1/4 cup butter, remaining 1/2 teaspoon salt, and remaining 1/4 teaspoon pepper; stir to combine. Cook over medium until butter is melted and mixture is reduced by half, about 2 minutes. Transfer wine mixture to a small saucepan. Add 1/2 cup water and any accumulated pork juices on cutting board. Bring to a boil over medium-high, and cook 5 minutes. Remove from heat.

Arrange pork loin (sliced or whole), roasted onions, and fresh thyme sprigs on a serving platter. Spoon wine sauce over top, and serve.