In a food processor combine the flour, salt, sugar, and butter. Pulse for about 10 seconds until the mixture resembles coarse sand. Slowly add the ice water while pulsing. Once the dough starts to pull together stop pulsing and remove from the food processor. Pack the dough into a disk shape, cover with plastic wrap, and refrigerate for 1 hour.

Once chilled, remove the dough from the fridge and roll out into a rectangle shape about 1/3 inch thick. Arrange the sliced peaches on the dough and then fold the sides of the dough over. Sprinkle with the sugar. Brush the sides of the dough with the egg wash or melted butter and bake in a 375 degree oven until the dough is golden brown and flaky.