Preheat your oven to 375°F (190°C). Line two large baking sheets with parchment paper or silicone baking mats to prevent the pies from sticking and to make cleanup easier.
In a medium mixing bowl, combine the pumpkin puree, brown sugar, pumpkin pie spice, and vanilla extract. Stir everything together until the mixture is smooth and the sugar is fully incorporated. Set this aside while you work on the dough.
Unroll the pie crusts on a lightly floured surface. Use a pumpkin-shaped cookie cutter (about 3-4 inches wide) to cut out as many shapes as possible. Re-roll the scraps once to get more shapes. You will need two pumpkin cutouts for every one hand pie.
Take half of your pumpkin cutouts and use a small, sharp paring knife to cut out Jack O Lantern faces. You can make simple triangles for eyes and a jagged line for a mouth. These will be the “tops” of your hand pies, allowing steam to escape while they bake.
Place the solid pumpkin shapes (the bottoms) onto the prepared baking sheets. Spoon about 1 tablespoon of the pumpkin filling into the center of each bottom piece, leaving a small border around the edges. Lightly brush the edges with a little bit of water or egg wash.
Place a carved face cutout on top of each filled bottom piece. Use the tines of a small fork to press and crimp the edges together firmly. This ensures the filling stays inside while baking and adds a decorative touch.
In a small bowl, whisk the egg and 1 tablespoon of water together. Lightly brush the top of each hand pie with the egg wash. If you like, sprinkle a little coarse sugar over the top for extra crunch. Bake for 18-22 minutes, or until the pastry is golden brown. Let them cool on the pan for at least 10 minutes before serving.