Directions

1. Preheat oven to 350°F, then line a 9" x 13" baking pan with parchment paper (up the sides as well) and spray with nonstick cooking spray.
2. For the crust, cream the butter and sugars until light in the bowl of an electric mixer fitted with the paddle attachment. Combine the flour and salt and, with the mixer on low, add to the butter mixture until just mixed. Dump the dough onto a well-floured board and gather into a ball. Flatten the dough with floured hands and press it into a 9" x 13" x 2" baking sheet.
3. Bake crust until lightly golden, 18 to 20 minutes. Remove from oven and let cool for 30 minutes.
4. For the filling, whisk together sugar, flour, eggs, lemon juice and lemon zest in a large mixing bowl until fully combined. Pour filling over the crust, return to the oven, and bake until firm, 24 to 26 minutes.
5. Remove from oven and refrigerate for 3 to 4 hours. Dust with powdered sugar, slice and serve.