In a medium bowl, stir together butter and sugar. Stir in yolks. Add flour, crystallized ginger, and salt, and stir until mixture just starts to come together (it will still be somewhat dry and crumbly).

Press dough into bottom and up sides of a 9-inch pie dish. Freeze for 20 minutes, or until firm, while you preheat oven to 375 degrees F.

Cover crust with a round of parchment paper and pie weights (I use about 2 cups of beans, which I store in a glass jar and re-purpose again and again). Bake, rotating halfway through, just until crust turns golden brown, 20-22 minutes. Allow to cool before adding the pie filling.

Process all ingredients in a blender or food processor. Pour into prepared pie crust and place in the oven. Cook in preheated 325 degree F. oven until the filling is just about set in the middle (it will continue cooking a bit after you take it out of the oven). This will take about 50-60 minutes; if the pie starts to brown, cover it loosely with foil while it finishes baking.

Allow the pie to cool in the refrigerator for at least 6 hours or overnight, and serve with homemade whipped cream to which you've added a healthy pinch of both ground ginger and cinnamon (I usually add a little organic powdered sugar to my whipped cream, too). 1 cup of organic cream makes about 2 cups of whipped cream, way more than enough for serving the pie.

Store leftovers in the refrigerator; in my experience, pumpkin pie does not freeze well.