Preheat the oven to 180 degrees C.
Form the pastry sheets into a square on the bench top, slightly overlapping the edges. Lightly roll the pastry to join the edges. Using a sharp knife make a 36cm pastry circle. Place on a lightly greased baking dish.
Combine the butter, gingernuts, brown sugar and pistachio nuts, Sprinkle a thin layer over a 25cm circle on the centre of the pastry base.
Place the fruit on top and sprinkle with the flour and sugar. Fold the outer edge of the pastry up over the fruit. Press the remaining gingernut mixture onto the top edge of the pastry.
Bake for 40 minutes or until the pastry is golden and cooked through.