Bœuf Wellington

03 — Method

1. Take the beef out of the fridge 1 hour ahead and season generously all over — ABSOLUTELY essential for a good sear.
2. Heat 3 tbsp of olive oil in the large cast-iron skillet over very high heat until just smoking and sear the beef 2 minutes on each side and the ends.
3. Set on a rack, brush generously with the mustard all over and let cool completely.
4. For the duxelles, very finely chop the 500 g (18 oz) of mushrooms by hand or in a food processor. Chop the 3 shallots and 3 garlic cloves and soften them in 50 g (2 oz) of butter for 5 minutes.
5. Add the mushrooms and cook over high heat for 20 minutes, stirring often, until COMPLETELY dry — ABSOLUTELY crucial so the pastry doesn’t go soggy. Deglaze with cognac.
6. Lay a large sheet of plastic wrap on the counter. Overlap the prosciutto into a 30 × 40 cm (12 × 16 in) rectangle and spread the cooled duxelles over it. Spread the beef with mi-cuit foie gras.
7. Set the beef on the duxelles and roll up tightly in the ham using the plastic wrap. Chill for 30 minutes. Preheat the oven to 220 °C (425 °F) fan.
8. Roll out the puff pastry and set the coated beef in the center. Wrap tightly, sealing the edges with beaten egg. Brush with the yolks and score a crosshatch. Bake for 25 minutes at 220 °C (425 °F). Rest for 10 minutes before slicing.