Prepare and blind bake the shortcrust pastry in a minimum 6 cup capacity baking dish - refer to Notes section for recipe link. Set aside to cool.Alternatively you can blind bake store-bought defrosted shortcrust pastry. 1 quantity shortcrust pastry
Meanwhile, heat the olive oil in a frying pan over high heat.
Add half of the cubed beef and cook, until browned and the liquid has evaporated (approx 5 minutes). Set aside in a separate bowl.Repeat with the remaining beef and set aside.Leave the excess fat in the frying pan. Place the onion, mushrooms and bacon into the frying pan over medium-high heat. Cook for 5 minutes or until softened and the liquid has evaporated. Add the cooked beef, beef stock, tomato paste and worcestershire sauce and stir.
Simmer uncovered for 45 minutes (or until starting to thicken), stirring occasionally.
Mix the cornflour and water together until completely dissolved.
Stir as you pour the cornflour and water into the beef mixture.
Allow to simmer and thicken (the mixture should be thick).
Season the mixture with salt and pepper and then set aside to cool completely (the mixture will continue to thicken on standing).
Place the puff pastry sheet on the bench to defrost.
Preheat oven to 200 degrees celsius (fan-forced).
Spoon the pie filling into the blind-baked pastry shell.
Place the sheet of puff pastry over the top of the pie and press the edges of the puff pastry together with the shortcrust pastry base.
Lightly brush over the beaten egg. Sprinkle with sesame seeds (optional).
Bake for 45 minutes or until golden.