Vegetable Stuffed Pork Tenderloin en Croute with Dijon Mustard Cream Sauce

For the Tenderloin and Pastry
1 pork tenderloin, trimmed
Salt and freshly ground pepper
2 Tablespoons vegetable oil
2 Tablespoons unsalted butter
1½ cup diced onions (1 large onion)
½ cup diced celery (about 2 stalks)
¾ cup diced, seeded green pepper
½ cup diced green onions (about 6)
¼ teaspoon dried thyme
1 teaspoon Essence or Creole seasoning
Pinch cayenne
2 Tablespoons chopped fresh parsley leaves
1 sheet frozen puff pastry
3 Tablespoons plain bread crumbs
¼ cup grated Parmesan cheese
1 large egg
1 Tablespoon water

For the Dijon Mustard Cream Sauce
2 Tablespoons all purpose flour
2 Tablespoons Dijon mustard
1¼ cups chicken broth
¾ cup heavy cream
¼ teaspoon salt
¼ teaspoon freshly ground pepper

For the Tenderloin and Pastry: Line a large baking sheet with aluminum foil and grease the center. If using Release, don't grease. Set aside.

Season the pork tenderloin on all sides with salt and pepper. Heat the vegetable oil in a large skillet over medium-high heat. Add the tenderloin; reduce the heat to medium, and brown evenly on all sides. Cook, turning frequently, until the well meat is seared on all sides, 10 to 12 minutes. Remove from skillet and allow to cool for at least 30 minutes.

In a clean, large skillet, heat 2 Tablespoons butter over medium heat. Add the onions, celery, bell pepper, and green onions. Sauté until vegetables are tender and any released juices have evaporated, 6 to 8 minutes, stirring frequently. Add the thyme, Essence, ¼ teaspoon pepper, a pinch of salt and a pinch of cayenne; cook for 1 additional minute. Remove the vegetables from the skillet and place in a bowl. Stir in the parsley; allow to cool for about 10 minutes. Set aside ½ cup of the vegetable mixture for the sauce.

On a lightly floured work surface, lightly roll sheet of the puff pastry to a 12 by 13-inch rectangle. Sprinkle the bread crumbs evenly over the puff pastry, leaving a 1-inch border around the edges. Spread the grated Parmesan cheese over the bread crumbs (the bread crumbs and cheese form a protective barrier between the meat and the puff pastry that keeps the puff pastry from getting soggy). Pat the seared tenderloins dry. Spread remaining half of the vegetable mixture onto the puff pastry, over the bread crumbs and cheese. Place tenderloin over the vegetables, so that it is parallel to the longer side of the pastry. Whisk together the egg and 1 Tablespoon of water. Brush the egg wash around the 1-inch border of the pastry. Gently lift the pastry around the tenderloin. Use the egg wash to seal the edges of the pastry. Cut away any excess pastry and seal the edges by pinching them together, and folding them under the tenderloin. Place the tenderloin, seam-side down on the prepared baking sheet. If desired, make a decorative cross-hatch pattern across the top of the pastry, bring careful not to cut through the pastry. Refrigerate the tenderloin and pastry for 30 minutes. (Note: May be refrigerated, for up to a day before baking.)

Preheat the oven to 400° F.

For the Dijon Mustard Cream Sauce: Heat the reserved ½ cup vegetables in a medium saucepan over medium-high heat. Add the flour and cook, stirring, for 2 minutes. Stir in the mustard and continue to cook for 1 more minute. Slowly whisk in the chicken broth and heavy cream. Bring mixture to a simmer and cook, over medium-low heat until sauce is reduced to about 1½ cups, about 20 minutes. Set sauce aside and serve warm or at room temperature.

Back to the Tenderloin: Brush the tops and sides of the pastry evenly with the remaining egg wash. Place the tenderloin in the preheated oven and bake for 40 to 45 minutes, or until golden brown. Remove from oven and let rest for 10 minutes before serving. Serve sliced, with the Dijon Mustard Cream Sauce. Yield: 4 servings.