Heat oven 190 C/375F. In a stand mixer add butter, icing sugar and 1/2 cup sugar into bowl. Beat at medium speed, scraping bowl often, until creamy.
Add egg and vanilla, continue beating until well mixed. Reduce speed to low, add flour, cream of tartar and baking soda. Beat until dough forms a ball.
Divide in half, roll out onto a floured board and roll to 1/4 inch thickness, cut out into shapes or use cookie cutters.
Bake in oven at 190 C , not fan forced for 10-15 minutes or until they are lightly browned. Baking time could vary if you have rolled a thicker cookie. You can either leave these cookies plain or decorate, what ever you like.