Preheat the oven to 350 degrees F. Line a 9-by-13-inch baking dish with aluminum foil and butter the foil.
Make the crust: Whisk the flour, confectioners' sugar and salt in a large bowl. Cut in the butter with your fingers to make a crumbly dough; press into the prepared baking dish. Bake 20 minutes, then transfer to a rack and let cool slightly.
Meanwhile, make the filling: Mix the eggs, granulated sugar and flour in a bowl with a fork. Mix in the lemon juice. Pour the filling over the crust and bake 25 more minutes; transfer to a rack and let cool completely. Sprinkle with confectioners' sugar. Lift out of the pan and cut into pieces.
Photograph by Paul Sirisalee
Courtesy of Food Network Magazine