In a heavy, medium size saucepan, gently boil maple syrup to 210° F or 240 degrees F. Use a candy thermometer to measure. Let cool slightly.

In a bowl, whisk together pumpkin, cinnamon, ginger, salt, cream, milk, and eggs; whisk in maple syrup. Pour pie into crust and bake in middle of oven 1 hour, or until filling is set but center still shakes slightly. (Filling will continue to set as pie cools.) Transfer pie to a rack to cool completely.