Preparation

• Preheat oven to 350°F. Line a 13 x 9 inch baking pan with parchment paper, leaving an overhang to form handles for lifting from the pan. Spray parchment with cooking spray or lightly butter.
• In a medium size mixing bowl, use a whisk to sift together flour, sugar, cornstarch and lemon zest. Using a pastry blender cut the cold butter into the mixture until it resembles peas. Press evenly into the prepared pan.
• Bake crust for 20 minutes just until lightly golden around the edge.
• Meanwhile prepare the filling: In the same bowl, whisk together sugar, lemon juice, eggs, flour, lemon zest and salt until fully blended. Pour over warm crust.
• Place back into the oven and bake for 25-35 minutes OR until the center is set when gently shaken.
• Cool completely in the pan on a wire rack. Lift from the pan using the parchment paper.
• Use a sharp knife to cut into 20 even squares or desired size pieces. Dust with powdered sugar and serve.
• Store leftovers in an airtight container, chilled for 3-5 days.