Ingredients

Instructions

1. 1

   Season the beef tenderloin generously with salt and pepper. Sear it in a very hot pan with a splash of oil on all sides until browned (about 2-3 minutes total). Remove from heat and brush immediately with Dijon mustard while hot. Set aside to rest.

2. 2

   To make the duxelles, sauté the finely chopped mushrooms and shallots in butter over medium-high heat. Cook until all the liquid has evaporated and the mixture is completely dry (this is critical to prevent soggy pastry). Stir in the thyme and season lightly. Let cool completely.

3. 3

   Lay out a large piece of plastic wrap on a flat surface. Arrange the prosciutto slices in a slightly overlapping rectangle large enough to encase the beef. Spread the cooled mushroom duxelles evenly over the prosciutto layer.

4. 4

   Place the seared beef in the center of the mushroom-covered prosciutto. Using the plastic wrap to assist, roll the prosciutto tightly around the beef. Twist the ends of the plastic to secure it into a tight log. Refrigerate for 30 minutes to set the shape.

5. 5

   Preheat your oven to 400°F (200°C). Roll out the puff pastry on a lightly floured surface to fit the beef log.

6. 6

   Remove the plastic from the beef log and place it in the center of the pastry. Brush the edges of the pastry with egg wash. Fold the pastry over the beef, sealing the edges tightly. Trim any excess pastry.

7. 7

   Place the wrapped beef seam-side down on a baking sheet lined with parchment paper. Brush the entire exterior with the remaining egg wash.

8. 8

   Score the top lightly with a knife for decoration, being careful not to cut all the way through to the meat. Sprinkle with a pinch of coarse salt.

9. 9

   Bake for 40-45 minutes, or until the pastry is deep golden brown and the internal temperature of the beef reaches 130°F (54°C) for medium-rare.

10. 10

    Remove from the oven and let rest for at least 15 minutes before slicing. This allows the juices to redistribute and keeps the pastry crisp.