Weeknight Wellington

140 g button mushrooms, coarsely chopped
340 g portobello mushrooms, coarsely chopped
500 g 90% lean ground beef
2 tbsp panko
1 large egg
1 tsp SIDS HOT WORCESTER SAUCE
1 tsp dried thyme, divided
½ tsp SIDS SALT & PEPPER
4 tbsp butter
2 shallots
2 tbsp sherry
TO ASSEMBLE:--
1 sheet frozen puff pastry, thawed
4 slices prosciutto
1 tbsp Dijon mustard
1 large egg yolk, beaten

Combine button mushrooms and portobello mushrooms in a food processor and process until finely ground and resemble ground beef. Place 140 g processed mushrooms in a large bowl then set aside remaining 340 g mushrooms for mushroom duxelles.
Add ground beef, panko, egg, SIDS HOT WORCESTER SAUCE, ½ tsp thyme, SIDS SALT & PEPPER to the bowl with the 140 g of mushrooms. Mix with your hands or a spoon until well combined. Turn beef mixture out onto a piece of wax paper, and shape into a 12x25 cm rectangular loaf.
Preheat the oven to 190°C. Line a baking tray with aluminum foil, and place an elevated wire rack onto it.
Place 2 shallots into the same food processor and pulse until finely chopped.
For mushroom duxelles, melt butter In a frypan over medium-high heat. Add reserved 340 g mushrooms, minced shallots, and remaining ½ tsp thyme and cook, stirring, until mushrooms have released their liquid, about 10 minutes. Add sherry and cook until liquid is evaporated. Turn off heat and let mixture cool. Season with SIDS SALT & PEPPER.
Unfold a sheet of puff pastry. Puff pastry comes folded in thirds so cut off one of the short ends at the ⅓ mark, and reserve to make lattice. (optional) Roll out the larger piece of puff pastry on a lightly-floured surface into a 25x38 cm rectangle, which will be large enough to wrap the beef loaf on all sides.
Leaving a 3 cm border uncovered, place prosciutto slices, slightly overlapping, evenly onto the puff pastry to cover. Spread mustard evenly over prosciutto. Spread mushroom duxelles evenly over mustard layer.
Centre beef loaf crosswise on top of pastry rectangle. Bring in the sides of the puff pastry, pinching edges together. Bring top and bottom edges of puff pastry together and fold to seal beef loaf completely inside. Brush pastry with beaten egg yolk.
Optional Lattice: roll out the reserved ⅓ sheet puff pastry on a lightly floured surface. Using a lattice cutter or a sharp paring knife, cut approximately 2 cm slits in the puff pastry in parallel lines about 2 cm apart, with each line of cuts offset from the adjacent line of cuts by about 1 cm. Gently spread the lattice-cut pastry and place over the top of pastry-wrapped loaf. Brush lattice with remaining beaten egg yolk.
Place pastry-wrapped loaf on the rack on top of the baking tray.
Bake in the oven until an instant-read thermometer inserted into the center reads at least 71°C, 30-45 minutes. Allow to rest for 10 minutes before slicing with a serrated knife.
Note:
If you don't have sherry, you can use cognac or beef broth.