Welsh Beef Wellington with Port and Mushroom Sauce

• 750g PGI Welsh Beef fillet
• 1 tbsp oil
• Salt and pepper
• 1-2 tbsp English mustard
• 40g dried porcini mushrooms
• 250ml boiling water
• 500g chestnut mushrooms
• 25g salted butter
• 2 cloves garlic, crushed
• Handful fresh thyme leaves
• 6 slices of prosciutto
• 500g ready made all butter puff pastry
• 1 egg, beaten

For the sauce:

• 300ml beef stock
• 200ml port or Madeira
• 1 tsp butter

• Rub the beef fillet with the oil and season well. Preheat a large frying pan over a high heat, add the meat and sear on all sides for around 5 minutes, until golden brown. Remove from the heat and transfer to a wire rack to cool. Once cooled (around 15 minutes) brush with the mustard.
• Meanwhile soak the porcini mushrooms in the boiling water until softened (around 20 minutes). Remove from the liquid (reserve for later), squeeze dry and chop finely.
• Finely chop the chestnut mushrooms or use a food processor. Heat the butter in a large frying pan and add the crushed garlic, chestnut mushrooms, porcini mushrooms, seasoning and thyme leaves. Leave to cook until the water has evaporated (around 20 minutes). Leave to cool completely and reserve a quarter of the mushrooms for the sauce.
• Lay 3 large sheets of cling film, overlapping on a work surface. Place the prosciutto on top, overlapping the edges to make one sheet large enough to wrap the fillet. Spread three quarters of the mushroom mixture over the prosciutto then sit the meat on top and spread with the remaining mushroom mixture on top. Roll the prosciutto around the beef using the cling film then wrap tightly and chill for 15 minutes.
• On a floured surface roll the pastry into a square or rectangle big enough to wrap the fillet – approximately 35cm square. Trim to neaten and roll the edges of the joining sides a little more thinly. Brush the edges with the beaten egg then remove the cling film from the meat and position it in the middle of the pastry. Wrap the pastry along the length of the fillet, overlapping slightly at the join. Fold up each end like a parcel and transfer to a lightly greased plate seam side down. Lightly score the pastry at 1cm intervals and decorate with the remaining pastry. Brush the wellington with egg wash all over, press on the decorations and brushing again with the egg wash. Chill for 20 minutes (or up to 12 hours if you wish).
• To make the sauce, pour the port into a pan with the reserved mushroom mix and bring to a boil. Simmer until the port has reduced then add the stock and porcini mushroom liquid and simmer for a further 10 minutes until syrupy. Season then stir in the butter. Set aside.
• Preheat the oven to 200ºC / 180ºC fan / Gas 6 and heat a baking tray for 5 minutes. Line the baking tray with greaseproof paper and lay the wellington on top. Cook for 35 minutes for rare or 40-45 minutes for medium. Cover with foil if the pastry starts to catch. Remove from the oven and leave to rest for 10 minutes before slicing and serving with the sauce.