Make the bottom crust: Put 1 cup of cold butter (cut into pieces) in the food processor with 1/4 teas. salt, 1/2 cup powdered sugar and 2 cups of flour.Process until the butter is in small pieces. (Should look like cornmeal).
Lightly press the crust into a 13 x 9 baking pan that has been greased or sprayed well.Bake at 350 degrees for 20 minutes. Set aside to cool slightly for 5 or 10 minutes.Turn the oven down to 325 degrees.
Meanwhile make the filling: Beat 4 eggs in a bowl and add 2 cups of sugar, 1/4 cup flour. Zest your lemon and add. Squeeze the juice. Add 6 TLBS of lemon juice and mix well. (You can use bottled lemon juice if you don't get enough juice out of your lemon.)Pour over the slightly cooked crust.
Bake at 325 for 25 minutes or until set. (It should not jiggle at all when you test it). When it is cool, sprinkle with powdered sugar.Cut into 32 pieces. (4 x 8)
Notes
I buy one lemon, zest it and use the juice. The rest of the lemon juice I need comes out of a bottle.