1 lb beef tenderloin
1 lb cremini mushrooms
1 sheet frozen puff pastry, thawed
6 slices prosciutto (thinly sliced)
2 egg yolks, lightly beaten
3 Tbsp Dijon mustard
3 Tbsp extra-virgin olive oil, divided
1 Tbsp milk
salt and freshly ground pepper, to taste
Preheat oven to 400 F degrees.
Place mushrooms in food processor and pulse until a semi-smooth paste forms.
Transfer to a medium size, pan over medium-high heat, and add 2 Tbsp olive oil. Add salt and pepper.
Cook until mushrooms release moisture and cook down. Set aside.
In the same pan, heat remaining 1 Tbsp olive oil, over high heat.
Add beef, seasoned with salt and pepper, and brown on all sides. Don't move or stir until it's well seared.
Set beef aside and brush all over with Dijon mustard.
Lay out a sheet of plastic wrap and place prosciutto, overlapping, on top of it.
Spread mushroom paste on top of prosciutto and place beef on top of paste.
Lift edge of plastic wrap, that's closest to you, up and over the meat.
Separate prosciutto from plastic wrap and roll it over itself. Tuck in the sides of prosciutto and finish wrapping beef.
Seal in plastic wrap and refrigerate 30 minutes.
Lay out puff pastry and roll/wrap beef. Keep puff pastry from overlapping, as it won't cook through. Trim excess, if needed.
Combine beaten eggs with 1 Tbsp milk. Brush on top and sides of beef roll.
Score the top of roll with a sharp knife, being careful not to pierce through the pastry.
Brush again with egg wash and place on baking sheet.
Bake for 25-35 minutes, or until internal temperature reaches 125-130 F degrees.
Let rest 10 minutes before slicing and serving.