Yield: 6 to 8 servings | 4 cups of gravy
To Prepare the Beef Wellington:
Tie the tenderloin with kitchen string in four places so that it holds its cylindrical shape while cooking. Rub it all over with olive oil, then season it liberally with salt and pepper. Heat a large, heavy skillet over high heat, and when hot add the beef and sear on all sides, including the ends, until well browned. Don’t skimp on this; it’s an important flavor-building step. Set the meat aside on a platter to cool. Combine the mushrooms, shallots and garlic in a food processor. Pulse until finely chopped. Add the butter and 2 tablespoons of olive oil to the pan you seared the beef in and heat over medium heat. Add the chopped mushroom mixture and 1 tablespoon of the thyme and sauté for 8 to 10 minutes, until most of the liquid has evaporated. Season with salt and pepper and set this mixture, commonly referred to as duxelles, aside to cool.
Spread a 1½-foot piece of plastic wrap on your work surface and arrange the prosciutto on top, overlapping the slices in a rectangle large enough to wrap around the beef tenderloin. Use a rubber spatula to cover the prosciutto evenly with a thin layer of the mushroom duxelles. Sprinkle the duxelles with salt, pepper and the remaining 2 table-spoons of thyme leaves. Remove the twine from the beef and smear it lightly all over with the mustard. Center the beef on the duxelles, then use the wrap to bring the prosciutto up and around the beef, tucking in the ends of the prosciutto as you roll. Twist the ends of the plastic and refrigerate the roll for 30 minutes.
On a lightly floured surface, roll the puff pastry out to about a ¼-inch thickness. (Depending on the size of your sheets you may have to overlap two sheets and press them together to fully enclose the meat.) Remove the plastic from the chilled beef, and place the roll in the center of the pastry. Bring the long sides up over the beef, enclosing it completely, brushing the seam with egg wash to seal. Trim the ends if necessary, then brush with egg wash and fold over to completely seal the package. Place the beef seam side down on a greased baking sheet and chill for 1 to 2 hours. Reserve the egg wash, covered, in the refrigerator.
Preheat the oven to 425°. Brush all of the pastry with the reserved egg wash, then cut a couple of slits in the top to allow the steam to escape as the beef cooks. Roast for 40 to 45 minutes, until the pastry is golden brown and the beef registers 125° on an instant-read meat thermometer. Let the Beef Wellington rest for 15 to 20 minutes before cutting into thick slices.
Serve with Mushroom Gravy*.
To Prepare the Mushroom Gravy:
Preheat the oven to 400°. Combine the bones, carrots, onions, celery, 3 of the garlic cloves and the thyme in a roasting pan. Season well with salt and pepper, and drizzle with olive oil. Roast in the oven for 30 to 40 minutes, until the bones are a deep golden brown. Transfer the pan to the stovetop and add the beef broth, wine and bay leaf. Bring to a boil, then simmer over medium heat for 25 to 30 minutes. Strain, discarding the solids, and skim off any fat. Heat the butter and 1 tablespoon extra-virgin olive oil in a skillet over high heat. Add the garlic, the shallots and the mushrooms. Season well with salt and pepper, and cook, stirring, for about 5 minutes, until the mushrooms are golden brown. Dust the mushrooms with the flour. Add 2 cups of the strained veal stock to the pan (freeze the remainder for another use) and stir to smooth out any lumps. Simmer until the flour is cooked and the gravy is thick and rich, about 10 minutes. Stir in the heavy cream. Serve hot.
Recipes from his new cookbook, Tyler Florence Family Meal (Rodale, 2010)