Ingredients:
For the Duxelles:
• 1 pound white button mushrooms
• 2 shallots, peeled and roughly chopped
• 4 cloves garlic, peeled and roughly chopped
• 2 tablespoons unsalted butter
• 2 tablespoons extra-virgin olive oil
• Kosher salt and freshly ground black pepper
For the Beef:
• One 2-pound center cut beef tenderloin (filet mignon), trimmed
• Extra-virgin olive oil
• Kosher salt and freshly ground black pepper
• Flour, for rolling out puff pastry
• 1 pound puff pastry, thawed if using frozen
• 1 large egg, lightly beaten
Directions:
For the Duxelles:
• Add mushrooms, shallots, and garlic, to a food processor and pulse until finely chopped.
• Add butter and olive oil to a large saute pan and set over medium heat.
• Add the shallot and mushroom mixture and saute for 8 to 10 minutes until most of the liquid has evaporated.
• Season with salt and pepper and set aside to cool.
For the Beef:
• To prepare the beef: Tie the tenderloin in 4 places so it holds its cylindrical shape while cooking.
• Drizzle with olive oil, then season with salt and pepper and sear all over, including the ends, in a hot, heavy-based skillet lightly coated with olive oil – about 2 to 3 minutes.
• Roll out the puff pastry to a thickness of 3-4mm.
• Spread the duxelles on the pastry.
• When the beef is seared, remove from heat, cut off twine.
• Allow to cool slightly, then place the beef fillet on top of the mushrooms.
• Fold over the longer sides of the pastry, brushing with egg wash to seal.
• Trim ends if necessary then brush with egg wash and fold over to completely seal the beef – saving ends to use as a decoration on top if desired.
• Place the beef seam side down on a baking sheet.
• Brush the top of the pastry with egg wash then make a couple of slits in the top of the pastry using the tip of a paring knife (this creates vents that will allow the steam to escape when cooking).
• If you have scraps of pastry left, use a pastry cutter to make the desired shapes, stick them on the top and glaze with the egg wash.
• Preheat oven to 400 degrees F.
• Bake for 20 minutes until pastry is golden brown and beef registers 125 degrees F on an instant-read thermometer.
• Remove from oven and rest for 10 minutes before slicing.
• Slice in 1-inch thick slices.