In a large mixing bowl, use a hand mixer to combine the flour, sugars, butter, oil, baking soda, cream of tartar, salt and vanilla in the order listed, mixing well after each addition. Shape the dough into 1-inch balls (the dough will be crumbly, but it should come together and hold a ball nicely); roll in additional granulated sugar.
Arrange the balls 2-inches apart on a baking sheet and flatten slightly with a glass dipped in sugar. Bake for 15 minutes or until light brown. Cool on the cookie sheet for 2 minutes. Remove to a wire rack to cool completely. Store in an airtight container.
Notes
Dip glass in water before dipping into sugar so that the sugar will adhere to the bottom of the glass.