# What You'll Need:
→ Beef
01 - 2 lb beef tenderloin, trimmed
02 - Salt and freshly ground black pepper, to taste
03 - 2 tbsp vegetable oil
→ Mushroom Duxelles
04 - 1 lb cremini or button mushrooms, finely chopped
05 - 2 shallots, minced
06 - 2 cloves garlic, minced
07 - 2 tbsp unsalted butter
08 - 2 tbsp fresh thyme leaves, chopped
09 - Salt and pepper, to taste
→ Assembly
10 - 10 slices prosciutto
11 - 2 tbsp Dijon mustard
12 - 14 oz puff pastry, thawed if frozen
13 - 1 large egg, beaten for egg wash
14 - Flour, for dusting
# Directions:
01 - Preheat oven to 425°F.
02 - Season beef tenderloin generously with salt and pepper. Heat vegetable oil in a heavy skillet over high heat. Sear beef on all sides for approximately 2 minutes per side until deeply browned. Remove from skillet and allow to cool completely.
03 - In the same skillet, melt butter over medium heat. Add shallots and garlic, sautéing for 1 minute until fragrant. Add chopped mushrooms and thyme, season with salt and pepper. Cook, stirring frequently, until all moisture evaporates and mixture reduces to a paste-like consistency, about 10 minutes. Set aside to cool.
04 - Lay a large sheet of plastic wrap on a clean work surface. Arrange prosciutto slices in slightly overlapping rows to form a rectangular layer slightly larger than the beef tenderloin.
05 - Spread cooled mushroom duxelles evenly over the entire surface of the prosciutto layer.
06 - Brush the cooled seared beef generously with Dijon mustard on all sides. Place the beef in the center of the duxelles-covered prosciutto.
07 - Using the plastic wrap as an aid, tightly roll the prosciutto and mushroom mixture around the beef to form a compact log. Twist the ends of the plastic wrap to seal securely. Refrigerate for 20 minutes to set.
08 - On a lightly floured surface, roll out puff pastry to a rectangle large enough to completely encase the beef log. Unwrap the chilled beef from plastic and position it in the center of the pastry.
09 - Fold puff pastry over the beef, trimming any excess dough. Press edges firmly to seal. Place the Wellington seam-side down on a parchment-lined baking sheet.
10 - Brush the entire surface of the pastry with beaten egg. Decorate with pastry scraps if desired. Return to refrigerator for 10 minutes to chill before baking.
11 - Bake for 40 to 45 minutes until pastry is deep golden brown. An instant-read thermometer inserted into the center should register 120°F for rare or 130°F for medium-rare.
12 - Allow the Wellington to rest for 10 to 15 minutes before slicing. This ensures juices redistribute and makes for cleaner slices.
