Buttermilk Pie Recipe

Cream together the butter and sugar. Add the egg yolks and beat well. Add the flour, salt, lemon juice and rind, and mix thoroughly. Add the buttermilk, then fold in the beaten egg whites. Pour the filling into the crust and bake in a preheated oven at 450 degrees for 10 minutes. Reduce heat to 350 degrees and continue to bake for 40 minutes