# What You 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 Steps:
01 - Preheat oven to 425°F.
02 - Season beef tenderloin with salt and pepper. Heat oil in heavy skillet over high heat. Sear beef on all sides 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, and cook until all moisture evaporates and mixture reaches paste-like consistency, approximately 10 minutes. Allow to cool.
04 - Lay large sheet of plastic wrap on work surface. Arrange prosciutto slices in slightly overlapping layer to form rectangle just larger than beef.
05 - Spread mushroom duxelles evenly over prosciutto.
06 - Brush cooled beef with Dijon mustard. Place beef on duxelles-covered prosciutto.
07 - Using plastic wrap, 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. Unwrap beef from plastic and place in center of pastry.
09 - Fold pastry over beef, trimming excess. Seal edges and place seam-side down on parchment-lined baking sheet.
10 - Brush pastry with egg wash. Decorate with pastry scraps if desired. Refrigerate for 10 minutes.
11 - Bake for 40 to 45 minutes until pastry is golden and instant-read thermometer inserted into beef reads 120°F for rare or 130°F for medium-rare.
12 - Allow to rest 10 to 15 minutes before slicing.