My grandmother was a purest when it came to her cookies and would turn in her grave if anything but dough ball and cookie stamp method was used. In fact, I have her old glass cookie stamp, which is an antique now.
Cream together the butter, powdered sugar, granulated sugar, eggs, vanilla and vegetable oil
Stir in salt, baking soda and cream of tartar.
Stir in flour. Cover and chill for 1 hour.
You can either roll out the dough and cut into shapes or you can roll heaping teaspoons of dough into balls. If you roll the dough into the balls, press the dough balls down with the bottom of a drinking glass or a cookie stamp. Dough will be soft so coat the glass or cookie stamp with some flour. If desired, sprinkle tops of cookies with colored decorator sugar.
Bake at 350 degrees for 8-10 minutes, or until cookies just barely start to turn golden brown around the edges.