Beef Wellington

Ingredients

• Beef tenderloin

  Separable lean and fat, trimmed to 1/8" fat, all grades, raw

  3 lb or 1.36kg

• Pancetta

  Sainsbury's

  2 oz or 57g

• Butter

  Unsalted

  2 tbsp or 28g

• Northwest Mix Mushrooms

  Mycological

  340g

• Shallots

  Raw

  1 shallot (medium) or 43g

• Extra Virgin Olive Oil

  Olive Oil - Tesco

  2 tbspn or 30g

• Garlic

  Raw

  2 clove or 6g

• Thyme Leaves

  Gel

  2 tsp or 24g

• Sherry

  Fino, Dry - Waitrose

  ½ oz or 14g

• Salt

  Table

  1 dash or 0.4g

• Pepper

  Spices, black

  1 dash or 0.1g

• Dijon mustard

  Grey poupon

  2 tbsp or 30g

• Italian Prosciutto

  Tesco

  10 Slice or 170g

• Egg

  Whole, fresh eggs

  1 large or 50g

• Puff pastry

  Frozen, ready-to-bake

  16 oz or 454g

Directions

1. Using kitchen twine, tie the tenderloin into a 12-inch log, folding the thinner end onto itself. (Use your hands to squeeze the meat into a log. You can be aggressive here.)
2. Place pancetta in a cold 12-inch skillet. Cook over medium heat, stirring occasionally, until pancetta starts to brown, 6 to 8 minutes.
3. Add butter, raise heat to high, and stir in mushrooms and shallot. Cook until the liquid released by the mushrooms has cooked off, 4 to 7 minutes. Reduce heat to medium and continue to cook until mushrooms are browned, stirring frequently, another 18 to 23 minutes. (Take your time here, you want a deep golden color for the best flavor.) Scrape bottom of the skillet as necessary to prevent burning.
4. If the lan looks dry, drizzle in a little olive oil, then stir in garlic and thyme leaves. Cook until fragrant, another 1 to 2 minutes. Stir in sherry, scraping up the browned bits on the bottom of the pan. Scrape mixture into a medium bowl to cool. (Do not add salt at this point.)
5. In the same skillet, heat 2 tablespoons olive oil over medium-high. Season beef generously with salt and pepper, then sear on all sides until browned, 1 to 2 minutes per side. Transfer to a plate, and cool slightly. Remove any twine. Brush meatball over with mustard.
6. On a clean work surface, overlap long sheets of plastic wrap (about 15-by-15 inches). Place prosciutto slices on top to make about a 14-by-7-inch rectangle, arranging them in an even layer and overlapping the pieces slightly. Spread cooled mushroom mixture on top.
7. Place beef along one long end of the prosciutto slices, and roll prosciutto tightly around beef. Wrap tightly with plastic wrap, twisting both ends like a candy wrapper. Chill in the refrigerator for at least 30 minutes and up to overnight.
8. Meanwhile, preheat oven to 400 degrees, and line a rimmed baking sheet with parchment paper. In a small bowl, whisk together egg and 1 teaspoon water. Lay puff pastry out on the prepared baking sheet, lightly draping over edges. (The pastry needs to be at least 14-inches long and 13-inches wide to cover the beef; if not, roll it out as needed.)
9. Carefully unwrap and place chilled log along the edge of one long side of puff pastry. Roll beef up tightly, then place it seam-side down on the baking sheet. Tuck puff pastry over the ends of the beef to cover them, pinching to seal and folding underneath. Brush top and sides of pastry with egg wash, and use a small sharp knife to cut a few slits into the top of the pastry.
10. Bake until a thermometer inserted in the center reads 115 degrees for rare, 25 to 35 minutes. (This timing will yield rare pieces at the thicker end and medium done pieces at the inner end of the loin.) Remove from oven and let rest for 10 minutes, then slice and serve while warm.