Leftover Prime Rib Pot Pie

Directions

1. In a large skillet over medium heat, add the oil, butter, carrots, celery, onions, and mushrooms, and cook, stirring occasionally, until the vegetables begin to caramelize and brown, 5 to 8 minutes. Add 1 teaspoon of thyme leaves, the parsley, and flour, and cook for 2 minutes stirring constantly, until fragrant and the flour is lightly golden brown.
2. Add the beef broth, Worcestershire, salt, and pepper, and bring to a simmer. Cook until thickened, and allow to reduce as needed. Note, the sauce will thin slightly once the beef is added and it cooks in the oven.
3. Remove from heat and stir in the beef, and peas. Let cool slightly, then transfer to a baking dish or cast-iron skillet. The pot pie can be cooled completely and covered and refrigerated at this point for up to 24 hours, or proceed to next steps for immediate cooking.
4. When ready to bake, preheat the oven to 425°F.
5. On a lightly floured surface, roll out the puff pastry sheets if needed, just slightly larger than the baking dish or cast-iron skillet. You may only need one sheet of pastry, depending on the size of the baking dish. Use a sharp knife to cut slits in the center to vent the pastry, and transfer to the baking dish, draping any excess pastry over the sides. The pastry can be trimmed or left hanging over the edges. Brush with egg wash, and top with reserved thyme leaves.
6. Place the baking dish on a rack in the center of the oven, and bake for 20 to 25 minutes until the pastry is deep golden brown and puffed. Reduce the oven temperature to 375°F, and continue baking for 10 to 15 minutes until the filling is bubbling.
7. Remove the baking dish from the oven and let cool slightly before serving. Enjoy!