With your mixer cream the butter until it is light and fluffy. Next cream in powder sugar, then the vanilla. Now mix in the flour. You want to do this quickly and as soon as you get pea sized balls stop mixing. Lightly spray a ceramic shortbread pan with Pam then pour the pea sized crumbs into the pan and smooth level. With the palm of your hand, firmly press down on the dough. Prick the entire surface with a fork and bake the shortbread right in the pan at 325 degrees for about 30-35 minutes. You want it nicely browned on top.
Let the shortbread cool in the pan for about 10 minutes. Using hot pads take the pan and flip over quickly onto a cutting board. Tap gently and it should fall right out. Cut shortbread right away, along the shortbread pan lines. Let cool and enjoy!