Preheat the oven to 425°F (218°C). Position a rack in the lower third of the oven and place a baking sheet on the rack to preheat. This step helps ensure the bottom crust bakes evenly.

In a large mixing bowl, whisk together the pumpkin purée, sweetened condensed milk, eggs, cinnamon, ginger, nutmeg, and salt. Continue whisking until the mixture is completely smooth and uniform.

Fit the unbaked pie crust into a 9-inch pie dish and crimp the edges as desired. Pour the prepared filling into the crust, smoothing the surface with a spatula. Carefully place the pie dish onto the preheated baking sheet.

Bake the pie at 425°F for 15 minutes. This initial high-heat bake helps set the crust and prevents sogginess.

Without removing the pie from the oven, reduce the temperature to 350°F (177°C). If the crust edges begin to brown excessively, cover them with aluminum foil or a pie shield. Continue baking for 30 to 35 minutes, or until the edges are set and the center has a slight wobble. A knife inserted near the center should come out mostly clean.

Transfer the pie to a cooling rack and allow it to cool completely at room temperature for approximately 2 hours. Once cooled, refrigerate the pie until fully chilled before slicing and serving.