2. Once the filling is cold, wet the edges of the pie dish with cold water. Place the pastry sheet over the pie dish, joining the 2 sheets together if necessary*, leaving about 2cm hanging over the sides. Push the pastry down on the sides of the dish to seal. Roughly fold the overhanging pastry back onto the pie top, to create a double edge. Make a couple of cuts in the top of the pastry. Brush the top with a little milk or beaten egg.