Preheat the oven to 350 degrees.
In a food processor, process first four ingredients until mixture begins to crumble. Press evenly onto bottom of 13 x 9 inch dish. Bake for about 20 minutes, or until golden. In a mixing bowl, whisk eggs and sugar until creamed. Stir in the lemon juice and flour.
Pour the lemon mixture over the hot shortbread.