Combine flour and salt in bowl. Cut in shortening until mixture is crumbly. Gradually add water, tossing with fork, until mixture comes together to form ball. Cover; refrigerate 30 minutes or longer.
Roll out dough on lightly floured surface to 11-inch round. Fit into 9-inch pie plate. Crimp edges.
Place baking sheet on middle rack in oven. Heat oven to 400 degrees F.
Combine sugar, flour and salt in bowl. Whisk in heavy cream and vanilla. Pour into pie shell. Place on preheated cookie sheet.
Bake in 400 degree F oven 15 minutes. Reduce temperature to 375 degrees F. Bake 25 to 30 minutes, until golden and just bubbly around edges. If edges brown too quickly, cover loosely with foil. Cool on rack. Refrigerate 3 hours or overnight. Serve with assorted berries if desired. Makes 12 servings.