Butter a 9 x 13 baking pan, then line the bottom and sides of the pan with parchment paper. This is optional but will make removing the bars from the pan much easier.

Make the crust by creaming the butter, sugar and salt in the bowl of an electric mixer until light and fluffy. Stir in the flour.

Using your hands, press the dough into the bottom of prepared pan. Chill the pan while the oven preheats to 350° degrees. Bake the crust for 12-15 minutes, until very lightly browned. Let cool on a wire rack. Leave the oven on.

Whisk together the eggs, sugar, lemon zest, lemon juice, and flour. Pour the lemon mixture over the crust and bake for about 35 minutes, until filling is set. Let cool to room temperature, then refrigerate at least one hour.

Cut into squares and dust with confectioners’ sugar. Store any leftovers in a covered container in the refrigerator.