Beef Wellington

Preheat the oven to 200°C.
 

Beef:

Heat a large frying pan over a high heat. Rub some oil  and freshly ground pepper over the beef and brown on all sides. Sprinkle with a little salt and set aside on a large plate to cool.
 

Spinach and mushroom filling:

Wipe frying pan with kitchen paper if necessary. Add the finely chopped mushrooms and cook, stirring regularly until all the water from the mushrooms has evaporated. Stir through the chopped herbs and season with pepper. Set aside to cool.
 

Pastry:

Spread the Dijon mustard evenly over browned beef. Place a piece of plastic wrap on the bench top and lay spinach leaves evenly over the plastic wrap. Then spread the mushroom mixture evenly over the spinach. Place the beef in the middle and using the plastic wrap to help you, roll up tightly. Place in the refrigerator for about 15 minutes.
On a lightly floured bench top, roll out the pastry large enough to fit around the meat. Brush egg wash over the edges, remove plastic wrap from the beef and place beef in the middle of the pastry. Cut out 4 corners from the pastry (this will be excess pastry once you fold), but being careful not to cut away too much, then fold the pastry over to completely enclose the beef, and turn over. Line a shallow roasting dish with some oil spray and place in the beef Wellington. Brush pastry well with egg wash. Score the top of the pastry with a small sharp knife, then place in the refrigerator for 5 minutes to set the pastry.

Remove from the refrigerator, brush once more with egg wash and sprinkle with a little flaky salt. Place in the oven and cook for 30 minutes. Remove from oven and rest for 10 minutes before slicing.
 

To serve:

Serve with steamed green vegetables and gravy.