Preheat your oven: Start by preheating your oven to 350°F (175°C). This temperature is perfect for baking the custard pie, ensuring the filling sets without overcooking. Make sure the oven is fully heated before placing the pie inside to ensure an even bake.
Heat the milk and cream: In a medium saucepan, combine the whole milk and heavy cream. Heat the mixture over medium heat until it is hot but not boiling. Stir occasionally to prevent the mixture from scalding. You want the milk and cream to reach a warm temperature, as this will help the custard ingredients come together more smoothly. Be careful not to let the mixture boil, as this could cause the cream to curdle or affect the custard texture.
Whisk together the egg mixture: While the milk and cream are heating, whisk together the sugar, eggs, cornstarch, vanilla extract, cinnamon, nutmeg, and salt in a large bowl. Whisk until the mixture is smooth and well combined. The cornstarch helps to thicken the custard, ensuring a creamy and stable texture. The vanilla and spices give the custard its signature holiday flavor, while the salt enhances the sweetness and richness of the filling. Be sure to mix until the ingredients are fully incorporated, as this ensures an even texture in the final pie.
Temper the eggs: Slowly pour the hot milk and cream mixture into the egg mixture, whisking continuously as you do. This process, called tempering, helps prevent the eggs from scrambling by gradually raising their temperature without shocking them with hot liquid. Be sure to pour the milk mixture slowly and whisk vigorously to achieve a smooth and uniform custard. This step is crucial for ensuring a silky, lump-free filling.
Strain the custard: Pour the combined custard mixture through a fine-mesh sieve into the unbaked pie crust. The sieve will catch any remaining bits of cooked egg or lumps, leaving you with a perfectly smooth custard filling. This step ensures that the texture of the pie is silky and lump-free, giving it a more refined, professional finish.
Bake the pie: Place the pie in the preheated oven and bake for 45-50 minutes. The custard should be just set, meaning the edges will be firm but the center will still have a slight wobble when you gently shake the pie. To test for doneness, insert a knife near the center of the pie. If it comes out clean, the pie is ready. If there is any custard sticking to the knife, bake for an additional 5-10 minutes, checking for doneness periodically. The pie will continue to set as it cools.
Cool the pie: Once the pie is baked to perfection, remove it from the oven and allow it to cool completely on a wire rack. Letting the pie cool gradually at room temperature will prevent it from cracking on the surface, preserving its smooth, custardy texture. While cooling, the pie will continue to firm up, so be patient as it reaches its perfect texture.
Chill the pie: For the best texture and flavor, refrigerate the pie for at least 2 hours before serving. Chilling the pie helps the custard fully set and allows the flavors to meld together. The pie will slice more cleanly once chilled, and the cool custard will offer a refreshing contrast to the warm spices and buttery crust.
