Preheat oven to 375°F.
In a large mixing bowl, mix together the pumpkin, sugar, salt, cinnamon, nutmeg, and, if using, ginger.
Add eggs and mix until well blended.
Pour in the evaporated milk, and stir until blended.
Pour the pumpkin batter into a prepared 9-inch pie crust.
Place in the oven (on a rimmed baking sheet if it looks like it might go over the edge), and bake for 50-55 minutes, or until a knife inserted into the center comes out clean.
Remove from oven and cool. Place in refrigerator and let the flavors meld for a day.