Position a rack in the center of the oven and preheat to 450˚F.
Put the pumpkin, sugar, cornstarch, salt, cinnamon, cloves, ginger, nutmeg, allspice, mace, and vanilla in the bowl of a stand mixer fitted with the paddle attachment. Paddle at low-medium speed for approximately 2 minutes.
With the motor running, pour in the milk in two additions. Stop the motor, scrape the sides of the bowl with a wooden spatula, restart, and paddle for an additional 2 minutes. Add the eggs and paddle until absorbed, approximately 2 additional minutes.
Pour the mixture into a 9-inch pie crust in a pan, and bake for 15 minutes, then lower the heat to 375˚F and bake until a finger dabbed onto the surface emerges clean, 30 to 40 minutes.
Remove the pie from the oven and let cool for 1 to 2 hours.
Slice and serve right away, or cover with plastic and refrigerate for up to 3 days.