In the bowl of a food processor fitted with the metal blade, combine the flour, sugar, and salt. Add the cold butter and pulse to form a coarse crumble.
Add the water and pulse it in, then let the food processor run just until the dough comes together. I use my Cuisinart Food Processor from Amazon for this recipe.
Divide the dough in two and transfer both pieces to your work surface. Shape each piece into a disk and wrap each in plastic wrap and chill for 30 hour.
After 30 minutes of chilling, retrieve one disk of dough. Roll the disk to a 14" circle. Transfer to buttered metal pie plate and fit it in place.
Trim and fold under the edges, then crimp the edge using your thumb and forefingers to create a wavy edge.
Place the pie shell in the fridge for 30 minutes until the pie shell is cold and hard.
Preheat the oven to 425 °F (220 °C). Move the oven rack to the lower ⅓ of the oven.
Retrieve the pie shell from the fridge. Line with a big square of parchment and fill the pie with dry beans or pie weights, enough to fill the pie shell up to the top of the crimped edges.
Par-bake the pie crust for 20 minutes.
Remove the pie shell from the oven and place on a cooling rack. Carefully lift off the parchment with the pie weights. Set aside. Put the pie shell back in the oven and continue to bake for another 3–5 minutes until the bottom looks dry and set.
Take the par-baked pie shell out of the oven. Lower the oven temperature to 375 °F (190 °C).
Whisk together the egg, water, and a pinch of salt while the pie shell is baking.
As soon as the par-baked pie crust comes out of the oven, brush the bottom and sides with egg wash but do not brush the edges! Let the pie shell cool completely while you make the filling. Save the leftover egg wash for the pie crust cutouts.
Pumpkin pie filling
In a large bowl (preferably one with a pouring spout like this), whisk together the filling ingredients until thick, creamy, and homogenous.
Once the par-baked pie shell has cooled, pour the filling in it.
Bake the pumpkin pie until the edges are set but the centre still jiggles a little. This takes about 35–40 minutes.
Take the pie out of the oven and place on a cooling wrack. Let the pie cool to room temperature, then refrigerate for several hours or overnight so that the pie sets properly before serving.
Decorate with pie cutouts before serving with whipped cream.
Pie crust cutouts
Preheat the oven to 425 ºF (220 °C).
On a lightly floured surface, roll the second disk of dough out until it's ¼–⅛" thick.
Cut out leaf shapes (or whatever shape you want). Place them on parchment-lined baking sheets, leaving a little space between them for air circulation.
Brush the cutouts with a thin layer of the leftover egg wash and sprinkle with cinnamon sugar.
Bake the cutouts until evenly golden brown and baked through, about 15–20 minutes.
Let the cutouts (and the pie) cool completely before decorating. You can store the leftover crust cutouts in an airtight container and eat them like cookies.
If you are short on time, use a store-bought pie crust. I prefer to use frozen pie crust from my local bakery, made with butter.
Use canned pumpkin purée, not canned pumpkin pie filling. If using homemade pumpkin purée (or even squash purée), make sure to strain it before measuring and using it to remove the excess water.
Par-bake the crust before filling to ensure that it will bake properly to a golden-brown crispy crust.
Bake the filled pie until the filling is set around the edges but still jiggles slightly in the middle.
I like to use the harvest cookie cutter set for creating decorative pie crust cookies to top fall pies and you can buy the set on Amazon.