Ingredients
2 lb beef sirloin
1 lb puff pastry
8 oz mushrooms, finely chopped
1 oz dried porcini mushrooms, soaked and finely chopped
4 oz prosciutto
2 tbsp Dijon mustard
2 tbsp olive oil
1 egg, beaten
1 small shallot, finely chopped
2 cloves garlic, finely minced
½ cup white wine
2 tbsp heavy cream
Salt and pepper, to taste
Directions
1. Preheat your oven to 400°F (200°C).
2. Season the sirloin with salt and pepper.
3. In a large skillet, heat 1 tbsp of olive oil over medium-high heat. Sear the sirloin on all sides until browned. Remove from the skillet and let it cool.
4. Brush the cooled sirloin with Dijon mustard and set aside.
5. In the same skillet, add the remaining 1 tbsp of olive oil. Sauté the shallots and garlic until fragrant, about 2 minutes.
6. Add the finely chopped mushrooms and soaked porcini mushrooms. Cook until the mixture is dry and the mushrooms are browned, about 10 minutes.
7. Pour in the white wine and cook until the liquid has evaporated. Stir in the heavy cream and cook until thickened. Remove from heat and let it cool completely.
8. Lay out the prosciutto on a sheet of plastic wrap, overlapping slightly. Spread the cooled mushroom mixture evenly over the prosciutto.
9. Place the sirloin on top of the mushroom-covered prosciutto. Using the plastic wrap, carefully roll everything to enclose the sirloin, then tightly wrap and refrigerate for about 30 minutes.
10. Roll out the puff pastry on a lightly floured surface to a size that will completely cover the wrapped sirloin.
11. Remove the plastic wrap from the sirloin and place it in the center of the puff pastry. Fold the pastry over the sirloin, sealing the edges with a bit of water if necessary.
12. Place the wrapped sirloin seam-side down on a baking sheet. Brush the pastry with the beaten egg.
13. Bake in the preheated oven for 25-30 minutes, or until the pastry is golden brown and the internal temperature of the meat reaches 125°F (51°C) for medium-rare.
14. Remove from the oven and let it rest for 10 minutes before slicing and serving.