Beef Wellington

Steps

1. 1
   Season the fillet with salt and pepper and sear it hard on every side for 4 minutes total, then brush it all over with mustard while hot and leave to cool completely.
2. 2
   Blitz the mushrooms to a fine rubble and cook them in the butter with the shallots and thyme.
3. 3
   Keep cooking, 20-25 minutes, until every drop of moisture has gone and the duxelles is a dry dark paste. Wet duxelles is the single reason Wellingtons go soggy. Add the brandy at the end and cook it off.
4. 4
   Lay overlapping prosciutto on cling film, spread the cooled duxelles over it, place the fillet on top and roll it into a tight cylinder using the film. Chill 30 minutes.
5. 5
   Roll the pastry, unwrap the cylinder onto it, and wrap, sealing the edges. Chill another 30 minutes.
6. 6
   Brush with egg yolk, score lightly, and chill once more for 15 minutes.
7. 7
   Bake at 200°C for 35-40 minutes for medium-rare — a probe should read 52°C at the centre.
8. 8
   Rest at least 15 minutes before slicing thickly.