Line a 9x13 inch baking dish with parchment paper and coat the paper with a non-stick spray. Set aside.

In a large bowl, combine flour, cornstarch, powdered sugar, salt and cubed butter. Using a pastry blender or a fork, mash butter into the dry ingredients until it is fully incorporated.

Pour the mixture into the prepared pan and pack it down firmly, allowing for some to come about 1/2 inch up the sides of the pan. Refrigerate the crust for 30 minutes and then bake at 350 degree F preheated oven for 30 minutes or until it develops a light golden brown color.

Allow the crust to cool while you prepare the filling. Reduce the oven temperature to 325 degree F.

In another large bowl, combine the eggs, sugar, and flour. In a blender, blend strawberries, lemon zest, lemon juice, and milk until well combined.

Pour the blended mixture into the egg mixture and stir well. Pour the filling over the partially baked crust and bake for 45 minutes, or until set. Baking time may vary depending on the oven.

Allow to cool for 30-45 minutes and remove from pan. Cut into 24 even squares and sprinkle with powdered sugar.