For the Crust:

1. Place the cubed butter, flour, sugar and salt.
2. Using a steel manual pastry blender to cut flour into crumbled pieces.
3. Add the cold water slowly to form into a dough.
4. Dust a clean surface with flour and roll out the dough to fit a 9 ½ -inch pie dish, with a little draping over the sides.
5. Pinch the dough around the sides and press down with a fork.
6. Pre-bake the crust for 10-12 minutes. Let cool on a rack before filling.

For the Filling:

1. Preheat Oven 350 degrees F.
2. Bake the sweet potatoes until fork tender; let cool and remove the skin.
3. In a large bowl place, the sweet potatoes; add the heavy cream, milk, eggs, brown sugar, cinnamon, nutmeg and vanilla.
4. Using an electric mixer on low speed mix until the ingredients are all incorporated.
5. Pour into the pie crust.
6. Bake approximately 1 hour and 15 minutes or until a knife inserted in the center comes out clean.
7. Let cool before serving.
8. Store in the refrigerator.