Traditional Beef Wellington.

Pat the beef dry, and season assertively with salt and pepper.

Heat a cast-iron skillet until smoking hot. Add neutral oil.

Sear the tenderloin on all sides until deeply browned, about ten minutes total.

Transfer the tenderloin to a tray, and brush all over with Dijon mustard while warm.

Let cool completely. Then, chill the tenderloin in the fridge for at least 30 minutes.

Working in batches if necessary, pulse the fresh mushrooms and dried porcini mushrooms in a food processor until very finely chopped.

In a large sauté pan, heat the olive oil and butter over medium heat.

Add the mushroom mixture to the pan, cover it with a lid, and sweat the moisture out of the mushrooms.

While mushrooms sweat, pulse the chestnuts, shallots, garlic, and thyme until finely chopped.

Remove the lid from the mushrooms, and continue to cook until the mixture is mostly dry. Add the chopped aromatics and Madeira wine, and stir to combine. Season with salt and pepper to taste.

Cook, stirring often, until the mixture is fragrant, dry, and darkened in color.

Let cool completely.

In a blender, combine all crêpe ingredients and blend until smooth, 15-20 seconds.

Let the batter rest for 15-30 minutes at room temperature. This relaxes the gluten and helps the crêpes spread thinly and cleanly.

Heat a large nonstick or seasoned skillet over medium heat. Add the tiniest swipe of butter to coat the bottom of the pan. Pour in half of the batter (½ cup or 120 milliliters). Then, immediately swirl to coat the pan in a thin layer of batter.

Cook 45-90 seconds or until the edges start to lift and the underside is lightly golden.

Flip and cook for another 20-30 seconds.

Repeat with the remaining batter, adding more butter to the pan if needed.

Let the cooked crêpes cool completely before wrapping (warm crêpes will create steam, which leads to sogginess). **You can make these a day ahead — store between parchment layers in the fridge.

Lay out a large sheet of plastic wrap on your work surface.

Arrange the prosciutto slices into a rectangle large enough to fully wrap the beef.

Spread a thin, even layer of duxelles over the prosciutto.

Place the crêpes on top, avoiding overlap.

Place the chilled tenderloin on the crêpes, and use the plastic wrap to roll the crêpes over the meat in a tight cylinder. Twist the ends to secure.

Chill 20-30 minutes, or ideally overnight, to help lock the shape of the Beef Wellington.

Dust a clean surface with flour.

Roll out one of the puff pastry sheets until it's ~⅛ inch (3 millimeter) thick, creating a neat rectangle.

Remove the beef roll from the plastic wrap, and place it in the center of the pastry.

Wrap the beef roll tightly with the puff pastry, sealing the seams well. Trim any excess pastry.

Chill the beef while you prepare the lattice.

Roll the second pastry into another ⅛ inch (3 millimeter) thick rectangle. With a lattice cutter, score the pastry all over.

Remove the Beef Wellington from the refrigerator, brush it lightly with egg yolk, and add the lattice. Brush the top of the lattice dough with yolk again.

Chill the Beef Wellington for at least 10-15 minutes or up to 30 minutes. Do not exceed 30 minutes or the pastry may become soggy.

Preheat the oven to 400°F (204°C), using a convection oven if possible.

Place the chilled Beef Wellington on a chilled sheet pan, and bake for one hour, or until the internal temp reaches 100-115°F (37-46°C) in the thickest part.

Rest 15-30 minutes before slicing to lock in the flavor and juices.

While the pastry cooks, combine the wine, shallot, garlic, thyme, and peppercorns in a small pot.

Simmer the mixture over medium heat until it reduces by half.

Add the stock, and continue to cook until the sauce reduces further and is glossy and coats the back of a spoon.

Strain the sauce, whisk in cold butter, and finish with a splash of aged balsamic. Season to taste.

Slice the Beef Wellington cleanly with a sharp serrated knife.

Spoon the sauce on a plate first, then nestle a slice of Beef Wellington on top. Enjoy warm!