Place a medium size frypan over medium heat
Clean any “silverskin” from the beef and season it with some thyme sprigs, salt and pepper
Pour a little olive oil in the pan and add the beef and seal over high heat until golden on all sides, once sealed set aside
In the bow of a food processor add some more sprigs of thyme and some roughly chopped mushrooms, blitz the mushrooms until fine and pour into a mixing bowl, repeat with any remaining mushrooms
Re-heat the frypan over medium high heat, add a little oil and place all of the mushroom mix in, season well with salt and pepper and cook the mushrooms for 4-5 mins, the mushrooms are ready when all the moisture has been cooked out in the pan
Set the mushrooms aside to cool
Set the oven to steam setting 100 degrees and place washed spinach leaved on a perforated tray, once the oven is hot steam the spinach for 4 mins, remove from the steamer and place into a bath of iced water to cool
Once cool squeeze the water out of the spinach
Once the mushrooms, spinach and beef are all cool lay out a large sheet of cling film and lay the prosciutto out evenly about the same length as your beef.
On top of the prosciutto spoon over the mushroom mix and press in to the prosciutto, next place the spinach over the mushrooms and even out the spinach layer to cover the mushrooms
Next place the beef fillet on top and with the aid of the cling film roll up the beef into a large tight sausage, pinch the ends and continue rolling to achieve a tight roll
Place the beef in the fridge for 30-40 mins or the freezer for 15 mins to slightly harden
Place 2 egg yolks into a bowl and set aside
Remove the beef from the fridge/freezer and discard the cling film
Lay out a sheet of puff pastry and place the beef roll into the middle, egg wash one end and roll the pastry around the beef,
keep the seam at the bottom
Seal the ends by folding the pastry in on itself, spray a tray with oil spray and place the beef on the tray, generously egg wash the entire surface
Place the wellington in a pre-heated oven combi setting 210 degrees for 20 mins
Once cooked remove from the oven and set aside to rest for at least 10 mins, change the oven setting to steam mode and place the broccolini on a perforated tray
Once the beef has rested place the broccolini in the oven and steam for 6 mins
Slice 2 cm from the end of the wellington and discard, then slice a 3-4cm slice from the beef, place on a plate
Remove the broccolini and season with olive oil and salt and serve a few stalks along side the beef, garnish with some fresh herbs and serve