Preheat oven to 350°.
Line a 9x13 baking pan with parchment paper allowing 2 inches overhang on the long sides or lightly grease.
Cream the butter with the sugars at medium speed until smooth and creamy, about 2-3 minutes.
Turn the mixer to low and beat in the sifted flour and salt mixture.
Transfer the dough to the pan and press it over the bottom and 1 ¼ inches up the side all around.
You can cover the dough with plastic wrap and use the bottom of a measuring cup to press.
Be sure that the corners are not too thick.
Refrigerate until firm.
Bake the crust for 30-35 minutes or until golden brown.
Halfway through the baking, use the back of a spoon to smooth the sides and corners of the crust.
When crust is done transfer to wire rack and let the crust cool before filling.
Chef's notes: The pecan bars can be refrigerated overnight. Serve chilled or at room temperature.