20g dried porcini or shiitake mushrooms(not to worry if you can't find any)
2sprigs of rosemary, chopped
230gcentre fillet of beef, trimmed
truffle oil (optional)
1tspEnglish mustard*if you don't like English mustard, you can switch it out for a chopped rosemary, salt and pepper rub. See below under 'Beef' for when to apply this)
1 x 320gall-butter puff pastry
1large free-range egg
1mug semi-skimmed milk
1mug plain flour (or self-raising)
Duxelles (mushroom paste)
Take your dried mushrooms and soak in a bowl of hot water for 10 mins until they soften, then drain, chop up and set to the side.
In a frying pan, add some oil, chopped onion and your chopped fresh mushrooms and cook until softened.
Now, in a processor add the onion, fresh mushrooms and 'dried' mushrooms and whizz until a smooth paste. You can add the truffle oil (to your taste) at this stage, if you want to.(You can do all this by hand, don't worry too much about it being a fine paste, it works just as well if a little rougher)
(**note: if you don't like English mustard this is where you can substitute for a rough rub of finely chopped rosemary, salt and pepper to season your beef)
In the same pan as the mushrooms were cooked, add some oil and fry the beef on all sides to seal and give it a nice brown colouring.Remove, brush with English mustard all over and set aside on a plate to cool.
Crack the egg into a bowl and add milk and flour and a pinch of salt and pepper. Whisk until smooth.
Place a large non-stick frying pan on medium heat, add a little oil and pour in a thin layer of batter. Make sure you get it to cover the whole pan, it needs to wrap your entire beef.Cook for a couple of minutes or until you see little bubbles on top and then flip over for 20 seconds or until golden underneath.Place to the side to cool.
Constructing the Beef Wellington
Preheat the oven to 220°C/425°F/gas 7.Leave your baking try inside so it's nice and hot when you place the Beef Wellington on it later.
Place a large sheet of clingfilm on a flat surface and lay your cooled pancake on top.Spread the mushroom duxelles (paste) over the pancake.Place the cooled beef in the middle of the pancake and using the clingfilm, roll it up and twist into a tight parcel.
On a flour-dusted surface, roll out your pastry large enough to roll the beef up in (approx the size of a tea towel) and still have a 1 -2 cm border.
Now, remove the clingfilm from the pancake-wrapped beef and place to one end of the pastry (leaving that 1 -2 cm border).Brush the beaten egg over the pastry border and the pancake, roll it up nice and tight. Trim the excess pastry and transfer to your (hot) large greased baking tray.Using a spoon or the other side of a knife gently score the pastry on top (not too hard or it will split open during cooking).Lastly, egg wash the pastry all over.
Place in the oven on the lower level, turn the temperature down to 200°C and cook for 40 mins.(*if you have a meat thermometer, then take it out of the oven at an internal temperature of 45°C as it will continue to cook while resting)
Rest for 10 mins and serve (large portions - it cuts far better)