If making from scratch, combine flour, salt, and cold butter in a food processor until crumbly. Slowly add ice water until the dough comes together. Wrap and chill for 30 minutes, then roll out and place in your pie dish. Pre-bake the crust at 375°F for 10 minutes to prevent sogginess.
Mix pumpkin puree, sugars, and spices in a large bowl until smooth. Whisk in the eggs, then gradually stir in evaporated milk until creamy. The filling should be silky without lumps.
Pour the filling into your crust and spread it evenly. The mixture will be slightly runny, but it firms up beautifully in the oven.
Start at 425°F for 15 minutes, then reduce heat to 350°F and bake for another 40 minutes. The edges should be firm, and the center should have a slight jiggle when done.
Place the pie on a cooling rack for at least 2 hours before slicing. This step is key because it allows the custard to set properly. Add your favorite toppings just before serving.