Prepare and roll out the pastry into a circle about 12 inches in diameter. Wrap pastry around the rolling pin. Unroll and ease pastry into a 9-inch pie plate, being careful not to stretch the pastry. Trim the pastry to 1/2 inch beyond edge of pie plate. Fold under extra pastry. Crimp edge as you like. Don't prick pastry. Line the pastry with a double thickness of foil.
Bake in a 450 degree F oven for 8 minutes. Remove foil; bake 4 to 5 minutes more or until set and dry. Reduce oven temperature to 350 degree F.
Meanwhile, in small mixing bowl, stir together sugar, flour, and salt. In large mixing bowl, beat butter and eggs with electric mixer until just combined.
Add sugar mixture; mix well. Gradually stir in buttermilk, vanilla, and lemon extract. Place partially baked pastry shell on the oven rack. Carefully pour filling into shell. Cover edge of pie with foil to prevent overbrowning.
Bake for 30 minutes. Remove the foil; bake pie for 10 to 15 minutes longer or until a knife inserted near center comes out clean. Cool on wire rack. Refrigerate within 2 hours; cover for longer storage. If you like, serve with raspberries. Makes 8 servings.