To make the shortcrust pastry, sift the flour into a large bowl.
Add the butter, vegetable shortening and lard cut into cubes, and use your fingertips to rub the fat with the flour until it resembles breadcrumbs.
Add the water, and bring everything together into a dough.
Cover with clingfilm, and refrigerate for at least 30 minutes.
Divide the dough into 7 smaller balls, and use a rolling pin to roll to roll into large discs (20 cm / 8 inches)
Preheat the oven at 160 degrees Celsius (320 degrees Fahrenheit).
Cut the beef and vegetables into small cubes, and mix everything together, then season with salt and pepper.
Divide and spoon the filling onto each dough disc, top the filling with a small cube of butter, then brush the edges with water, and fold the dough over.
Crimp the pasties by pinching the fold between your thumb and fore finger.
Brush the pasties with beaten egg, then transfer to a large baking tray lined with non-stick paper.
Bake for about one hour on the middle rack of the oven, or until the pastry is golden and the filling is cooked through.