Prepare Cornmeal Crust. On a lightly floured surface roll pastry into a 12-inch circle. Ease pastry circle into a 9-inch pie plate without stretching it. Trim pastry to 1/2 inch beyond edge of pie plate. Fold under extra pastry. Crimp edge as desired.
Preheat oven to 350 degrees F. In a small saucepan heat butter over medium heat until foamy. Reduce heat and continue heating until butter turns a dark golden brown. Remove from heat; cool.
In a medium bowl whisk together eggs, brown sugar, corn syrup, maple syrup, vanilla, salt, and browned butter. Sprinkle dates and pecans onto bottom of pastry-lined pie plate. Pour egg mixture over dates and pecans. Cover edge of pie loosely with foil.
Bake for 25 minutes; remove foil. Bake for 20 to 25 minutes more or until a knife inserted near the center comes out clean. Cool on a wire rack. If desired, serve with whipped cream. Cover and chill within 2 hours.
In a medium bowl stir together flour, cornmeal, sugar, and salt. Using a pastry blender, cut in shortening until pieces are pea size. Gradually add buttermilk to flour mixture, tossing gently with a fork. Add the water, 1 tablespoon at a time, tossing gently until all of the flour mixture is moistened. Gather flour mixture into a ball, kneading gently until it holds together.