Add mushrooms and cook over high heat until all moisture has
gone
Add sherry and cook until dry once more
Taste and season with salt and pepper
Add tarragon and set to one side to cool
Beef
Next sear the beef in very hot frying pan, seasoning with salt
and pepper until a rich colour has formed then add the remaining
butter and baste the foaming butter over beef for 3 to 4
minutes
Remove from the pan and chill
To Assemble
Roll out pastry to a oblong approximately 30cm square and 5mm
thick, making sure the pastry will wrap around the meat and
duxelle
Next, trim and lay the pancakes onto the pastry, leaving a 10
cm pastry edge at top and bottom
Next, spread a thin layer of duxelle over the pancakes
Position the beef two thirds of the way up the duxelle
Brush the edges of pastry with egg wash
Taking care not to tear the pastry start at the point nearest
to you and fold the parcel over encasing the entire filling
Gently seal the folded edge furthest away from you using the
outer side of your small finger
Next gently indent into the sealed edge a table fork creating a
secure seal
Trim the excess pastry away 10mm from fold
Carefully score the pastry top with a sharp knife, making sure
you don't go through the pastry and expose the filling
Brush with egg wash and place onto a baking tray lined with
parchment paper
Bake in a pre-heated oven, 185ºc fan on for approximately 30
minutes, the pastry should be golden brown and brittle
The core temperature of the beef should be 54ºc after resting
for 10 minutes so suggest removing from the oven when you get to
50ºc for a beautiful and pink beef wellington