Preheat oven to 400°F and set the rack to the lowest position.
In a small bowl, prepare the egg wash. Beat 1 egg with 2 teaspoons of water and set aside.
1 large egg, 2 teaspoons water
Place the pie dough into an ungreased 9 or 10-inch pie dish. Gently press the pie dough into the bottom and up the sides of the dish. Trim any excess crust from the edges. If using an already prepared pie crust in a tin, simply make sure to take it out of the refrigerator.
1 (9-inch) refrigerated pie crust
Pinch the edges of the dough around the pie dish. Brush the pie dough edges with the egg wash. Set aside.
In a large bowl, whisk together the pumpkin puree, 2 eggs, evaporated milk, and brown sugar.
15 ounces pumpkin puree, 2 large eggs, 12 ounces evaporated milk, ¾ cup brown sugar
Add the cornstarch, pumpkin pie spice, vanilla, and salt. Stir to combine.
1 tablespoon cornstarch, 2 teaspoons pumpkin pie spice, 1 teaspoon pure vanilla extract, ½ teaspoon kosher salt
Pour the filling into the pie shell, and bake for 15 minutes.
Reduce the oven temperature to 350°F, cover the crust with aluminum foil or a pie shield, and bake for another 40-45 minutes.
Let the pie cool for 2 hours before serving.