In the mixing bowl of a Stand Mixer, or using a hand mixer, add the Butter, Sugar, and Egg, and blend, cream butter with the paddle attachment until smooth, and creamy. Add the Vanilla, and mix until blended. In a separate bowl, using a measuring cup, add the Flour, and Salt, and mix well to blend. Add the Flour mixture to the mixing bowl, and mix until blended, and smooth. Place a large piece of Parchment paper on your work surface, and sprinkle with enough flour to coat the surface. Divide dough and place half of the Cookie dough on the Parchment paper, and with a Floured Rolling Pin, roll the Dough to 1/2 inch thickness.