To a food processor, add in the flour, sugar, salt, and cubed butter. Pulse the mixture together until you have small pea-sized chunks of butter throughout the mixture.
Add in the water 1 tbsp. at a time, just until the dough comes together.
Divide the dough into 2 equally sized pieces and form each into a ball. Slightly flatten each ball of dough, then cover it tightly in plastic wrap.
Chill the dough in the fridge for at least 1 hour, and up to overnight.
Preheat the oven to 350°F / 175°C.
Take out one of the pie crusts and place it on a lightly floured work surface. Roll it out until it is 12” in diameter.
Transfer the dough into a deep 9” pie dish. Use your fingers to flute the edges, then poke holes in the dough with a fork. Place the crust back into the fridge.
Take the other pie dough out of the fridge and roll it out into a 9” circle. Use cookie cutters or stamps to cut out little leaves, pumpkins, or any design you want on top of the pie.
Form the extra scraps back into a ball, re-roll, and cut out more shapes.
Place the shapes on a parchment lined baking sheet.
Whisk together the egg and 1 tbsp. milk, then brush each cut out with some of the egg wash.
Place the cut outs and the fluted pie crust into the oven. Bake for 10-15 minutes, or until the pie crust just starts to turn golden brown, and the pie cut outs are golden brown. Place the pie crust cut outs in an airtight container and save them on the side until the pie is ready to be served.