First, gather all of the ingredients together.

Next, finely chop the wild mushrooms and squeeze through a clean tea towel to remove as much water as you can.

Now melt 3/5 of the butter in a small skillet or frying pan and add the chopped shallots and mushrooms.

Once the shallots and mushrooms have softened add the sherry and reduce this down until itis fully reduced. Set aside to cool.

Season the tenderloin.

Now, melt the remaining butter in a small plan and seal the tenderloin on all sides. Set aside to rest.

Roll the pastry thin and flat.

Spoon a small amount of the duxelle on to one end of the pastry.

Add the steak and remaining duxelle.

Cut the pastry and so ready to make a parcel and egg wash the ends. Form the parcel and place on a baking tray.

Place the baking tray in a fridge for 30 minutes. At the same time heat your oven to 200C / 180C Fan.

After 30 minutes bake the Wellington to your liking. 15 minutes rare, 20 minutes medium rare, 25 minutes medium and so on... Now serve and enjoy!