Set oven to 190C and line 3 trays with baking paper.
In a large bowl, whisk the flour, cream of tartar, baking powder and salt together.
Using an electric mixer, beat the butter, brown sugar and white sugar on medium-high speed until fluffy and light for approximately 3 minutes.
Beat in the eggs and the vanilla extract.
Remove bowl from the mixer and add the flour mixture. Using a wooden spoon, stir until just combined.
In a small shallow bowl, add the extra white sugar and cinnamon and stir until well blended
Form the biscuit dough into small balls, equivalent to roughly 1 tablespoon of mixture (about the same size as a rum ball).
Roll the balls in the sugar/cinnamon mixture and place on the prepared baking trays. Leave approximately 4 – 5 cm between each ball in both directions to allow room for spreading. I usually do 9 balls (or biscuits)/tray.
Bake for approximately 11 – 12 minutes or until the biscuits are golden brown.
Remove tray from oven and allow the biscuits to sit for approximately 3 minutes. Transfer biscuits to a wire rack to cool completely.
This recipe makes approximately 50 – 55 biscuits depending on the size you roll the balls and the biscuits can be frozen.
Recipe by Mrs Organised at http://www.mrsorganised.com.au/2017/02/03/snickerdoodles/