Sugar Cookie Drops

Preheat oven to 350 degrees F. In a large bowl, cream together the butter, oil confectioners' sugar, and 1 cup white sugar until light and fluffy. Beat in eggs, one at a time, and stir in vanilla. Combine the flour, baking soda, and cream of tartar; stir into the creamed mixture. Roll dough into 1 inch balls, and then roll the balls in the remaining white sugar. Place onto ungreased cookie sheets, and flatten with a fork. Bake for 10 to 12 minutes in the preheated oven, or until the edges begin to brown. Cool on wire racks.