Preheat oven to 230ºC . Line 23 cm pie plate with pastry. Trim and flute edges; do NOT prick pastry. With rotary beater, beat flour, sugar and sour cream (use commercial sour cream from store). Arrange flat edge of peach quarters on pastry in concentric circles. Pour sour cream on top. Bake 15 minutes at 230ºC , then lower heat to 180ºC and bake 25-30 minutes or till filling is set. Sprinkle brown sugar over hot pie. Broil 1-2 minutes till sugar is melted. Serve warm.