18 oz mushrooms (cremini, shiitake, morsel, hen of the woods)
1 shallot
4 cloves garlic, minced
1 tbsp fresh rosemary
½ tsp fresh thyme
½ tsp salt
½ tsp pepper
3 oz (6 slices) of Bresaola or Prosciutto
Puff Pastry
3 sheets of filo
1 egg (beaten with 1 tsp water)
Instructions
Using a food processor or finely chop mushrooms, shallot, garlic, rosemary, and thyme. Preheat a cast iron skillet and add 2 tbsp oil. Pour in mushrooms and season with salt and pepper. Cook over medium heat without stirring for 6 minutes. Flip and cook for an additional 5 minutes until browned and reduced. Set aside.
Wipe the cast iron clean and add 1 tbsp oil or ghee. Sear the beef tenderloin for 1 minute on each side over medium-high heat. Immediately place it in the fridge to halt the cooking process.
Once cool, coat the tenderloin with Dijon mustard.Set aside.
Lay a 10" x 15" plastic wrap on a clean surface. Place three layers of filo dough on top, followed by the prosciutto or Bresaola, and then a thin layer of the duxelles (mushroom mixture).
Place the beef tenderloin at the edge facing you. Lift the corner of the plastic wrap and roll away from yourself. Ensure the plastic wrap is pulled out after each roll. Cover tightly with plastic wrap and refrigerate for 30 minutes.
Preheat the oven to 425°F.
Lightly flour a clean surface and roll out the puff pastry to 10" x 15", 1/8" thick. Brush the puff pastry with the egg wash.
Remove the tenderloin from the fridge and unwrap. Place it on the edge of the puff pastry, then roll it up until the entire tenderloin is covered. Press the seam of the puff pastry to secure the wellington. Fold the edges like an envelope, and tuck them under. Ensure there are no gaps. Brush the top and sides with egg wash. Use a knife to add a decorative design, being careful not to cut through the pastry.
Pierce a small corner of the top left and right corner to create ventilation for steam.
Bake at 425°F for 30 minutes for rare or 40 minutes for medium-rare. The internal temperature should be 125-130°F for rare or 140-150°F for medium-rare. Place the roast on a cooling rack and let it rest for 20 minutes.
