# What You'll Need:
→ Beef
01 - 2 lb beef tenderloin, trimmed
02 - Salt and freshly ground black pepper to taste
03 - 2 tablespoons vegetable oil
→ Mushroom Duxelles
04 - 1 lb cremini or button mushrooms, finely chopped
05 - 2 shallots, minced
06 - 2 cloves garlic, minced
07 - 2 tablespoons unsalted butter
08 - 2 tablespoons fresh thyme leaves, chopped
09 - Salt and pepper to taste
→ Assembly
10 - 10 slices prosciutto
11 - 2 tablespoons Dijon mustard
12 - 1 sheet puff pastry, approximately 14 oz, thawed if frozen
13 - 1 large egg, beaten for egg wash
14 - Flour for dusting
# How to Prepare:
01 - Set oven to 425°F and allow to reach full temperature.
02 - Season beef with salt and pepper. Heat oil in heavy skillet over high heat. Sear beef on all sides for approximately 2 minutes per side until browned. Remove and allow to cool completely.
03 - In the same skillet, melt butter over medium heat. Add shallots and garlic, sauté for 1 minute. Add mushrooms and thyme, season with salt and pepper. Cook until all moisture evaporates and mixture reaches paste consistency, approximately 10 minutes. Allow to cool.
04 - Lay plastic wrap on work surface. Arrange prosciutto slices in slightly overlapping layer to form rectangle just larger than beef dimensions.
05 - Spread cooled mushroom duxelles evenly over prosciutto base.
06 - Brush cooled beef with Dijon mustard and place on duxelles-covered prosciutto.
07 - Using plastic wrap as guide, roll prosciutto and mushrooms around beef into tight log. Twist ends to seal and refrigerate for 20 minutes.
08 - Roll out puff pastry on floured surface to rectangle large enough to fully encase beef bundle. Unwrap beef from plastic and position in center of pastry.
09 - Fold pastry over beef, trim excess, and seal edges. Place seam-side down on parchment-lined baking sheet.
10 - Brush pastry surface with beaten egg. Decorate with pastry scraps if desired. Refrigerate for 10 minutes before baking.
11 - Bake for 40 to 45 minutes until pastry achieves golden color and instant-read thermometer inserted into beef center reads 120°F for rare or 130°F for medium-rare.
12 - Remove from oven and allow to rest for 10 to 15 minutes before slicing to retain juices.