In a medium bowl mix the flour, powdered sugar, dash of salt, and the melted butter.
Press the ingredients into the bottom of a greased 8 inch square baking dish. Bake crust for about 25 minutes, or until golden brown.
For the filling:
Cut both ends off of the lemon, cut it in half and remove all the seeds. Slice into thin slices.
Put lemon slices into processor or blender with sugar and lemon juice and purée until liquified.
Add the eggs, cornstarch, dash of salt, and melted butter and blend until smooth.
Pour onto hot crust and bake 25 - 30 minutes, or until filling is not longer jiggly. Cool and cut into bars. Dust with powdered sugar just before serving.
Disclaimer: Nutritional values (per serving) are approximates only and will vary based on cooking methods and brands of ingredients used.