To make the crust

Preheat the oven to 325 degrees.

Combine the flour and the powdered sugar in the bowl of an electric mixer. Using the paddle attachment, add the butter and mix on low speed until mixture is the size of small peas. Press the crust into the bottom of a 9- by 13-inch pan.

Bake the crust for about 20 to 25 minutes, until golden brown.

To make the filling

Decrease the oven temperature to 300 degrees.

Whisk together the eggs and sugar in a large bowl until smooth. Stir in the lemon juice and then the flour. Pour the lemon filling on top of the crust.

Bake the lemon bars for about 40 minutes, until the lemon filling is set.

Allow them to cool for ½ hour, slice into squares, and dust with the ¼ cup powdered sugar.