Add plain flour, salt and butter to mixer bowl. Mix for 30 sec/speed 2/MC on.
Add cold water and mix for a further 2 min/dough function/MC off.
Shape the dough into a disc, wrap it in plastic wrap, and refrigerate for at least 30 min.
Preheat fan-forced oven to 180°C or 350°F.
Add all remaining ingredients except egg to mixer bowl. Combine for 10 sec/reverse/speed 1- using spatula to help combine.
On a lightly floured surface, roll out the pastry to about 3mm thickness.
Cut out 10 circles at 18cm rounds (or 8 larger at 22cm rounds).
Divide mixture by 10. Place 1/10 of the filling (approx. 2 Tbsp) on one half of each pastry circle, leaving a 2-3cm border around the edge.
Brush the edges with a little water, then fold the pastry over to enclose the filling. Press the edges to seal, and crimp them so no holes
Place the pasties on a baking tray lined with baking paper. Brush the tops of the pasties with the beaten egg for a golden finish.
Bake for 45 min or until golden brown.