1, 3-3.5-pound center-cut beef tenderloin (filet mignon), trimmed of any excess fat
1 tablespoon salt, divided
1 tablespoon black pepper, divided
3 tablespoons olive oil
2 tablespoons butter
1 large shallot, minced
2-pounds wild mushrooms (I use a mix of shitake, oyster, cremini, etc…), minced
⅓ cup dry red wine
3 teaspoons fresh thyme leaves removed from stem
½-pound Prosciutto or Parma ham, thinly sliced (about 12 slices)
2 tablespoons Dijon mustard
1 sheet frozen puff pastry, thawed (plus another sheet for decorations – optional)
1 egg and 1 egg yolk, beaten
5 tablespoons tri-color peppercorns, crushed
5 tablespoons butter
1 large beef bouillon cube
5 tablespoons Dijon mustard
1 cup brandy
2 cups heavy cream
Using kitchen string, tie the tenderloin at 2” intervals so the meat holds its cylindrical shape. Season liberally on all sides with salt and pepper.
Heat 3 tablespoons of the olive oil in a large cast iron skillet over medium high heat until the oil is almost smoking. Add the tenderloin and sear on all sides, including the ends, about 1-2 minutes per side. Set aside to cool.
Prepare the mushroom duxelle (mushroom pate). Heat remaining 2 tablespoon olive oil and butter in the same skillet you seared the beef in. Add the shallots to the pan and sauté until soft.
Place your mushrooms in the bowl of a food processor and pulse until finely chopped. Add them to the shallots and cook, stirring frequently until most of the moisture has cooked off, about 10 minutes. Add the red wine and thyme leaves to the pan and cook again, stirring until the mushroom mixture is mostly dry and forms a paste. Season with 1 teaspoon each salt and pepper or to taste. Cool completely in the refrigerator (or on your back steps if it is December and you live in the Northeast!!).
Place several overlapping layers of cling wrap on your countertop that is about 6” longer than your tenderloin on each end and wide enough to wrap the entire tenderloin securely (about 18”). In the center of the cling wrap, place overlapping layers of the prosciutto forming a large rectangle about 1” longer than your tenderloin on each end and wide enough to wrap around the meat and totally cover it (about 12”).
Spread your cooled mushroom duxelle in a thin, even layer over the prosciutto. Press any extra liquid out of the mushrooms with paper towels.
Cut the kitchen string off the tenderloin and discard. Spread the mustard all over the tenderloin and place it on one end of the mushrooms (1” mushrooms and prosciutto on either side). Taking the end of the saran wrap, on the long side of the tenderloin, roll the tenderloin to wrap the prosciutto-mushroom layer tightly around it. Twist the ends of the cling to form a tight tube. Refrigerate for 3 hours to set.
Roll out the puff pastry dough into a rectangle ¼” thick and about 2” longer that the tenderloin on each end and wide enough to wrap around the meat fully, about 14-18”. Create another overlapping layer of cling wrap on your counter (same as the first one) and place the dough in the center.
Carefully unwrap the meat and place on the long end of the puff pastry with the 2” excess on either end. Again, using the saran wrap, tightly roll the puff pastry around the meat and tuck in the ends to seal, cutting off any excess pastry (you can use any excess dough to make decorations on top later). Again, twist the ends of the saran wrap to tightly seal. Refrigerate for at least 1 hour or up to overnight.
Preheat oven to 400 degrees.
Remove the dough covered wellington from the cling wrap and place, seam-side down on a baking sheet lined with parchment paper and lightly coated with olive oil. Brush the egg wash all over the top of the dough. Score the top of the dough with a fork or knife which will create a pretty design when the dough puffs up during baking. You can also roll out any excess dough (or another sheet) and cut out designs such as flowers, leaves, or holly and place on top of the dough. Brush and decorations with more of the egg wash so that all of the dough is covered.
Bake for 40-45 minutes until the meat is 130-135 degrees for medium rare. Note it is very important that the meat is COLD when it goes into the oven so the meat does not overcook ‘inside’ before the dough is beautifully browned.
Let rest for 10 minutes and carve into slices. Serve as is with mashed potatoes or make the following sauce and drizzle over the top of each slice:
Put peppercorns in a ziplock bag and smash with a rolling pin or brick until crushed.
Melt the butter in a large saucepan. Crumble in the beef bouillon cube. Whisk to combine.
Add the Dijon mustard to the pan and whisk it around a bit. Pour in the brandy. Whisk the Dijon and brandy together until combined, and then let it bubble for about 45 seconds or so. Then pour in the heavy cream and the crushed peppercorns. Whisk it all together, allowing it to bubble for 5-8 minutes to thicken.
Depending on the dish you are making, you may have some pan juices or drippings. Before serving whisk drippings into the sauce. Serve hot with extra on the side… it’s that good!