Darren McGrady's Original Balmoral Shortbread Cookies

Comments
This is the original recipe, as opposed to the modified one I have posted. 
Ingredients
225g (8oz) plain flour
225g (8oz) unsalted butter, cut into 1/2" cubes
115g (4oz) icing sugar (some people prefer granulated sugar for shortbread)
115g (4oz) corn starch
1 tsp. salt
1 - 2  tsp. vanilla paste (or vanilla extract)


Directions
  1. Preheat the oven to 325°  (Some version of this call for 350°.) Add all of the ingredients, except the vanilla in a large bowl and mix together until it resembles breadcrumbs.
  2. Then add the vanilla and lightly bring together.
  3. Tip out onto a lightly floured surface and gently knead to form a dough.
  4. Dust a classic Scottish shortbread mold with flour and press the dough into the mold. Alternatively, roll the dough out and by hand form a circle shape.
  5. Gently turn out the shortbread and place it onto a lined baking tray.
  6. Using a fork, prick the surface of the shortbread all over and bake in the oven for around 20 minutes or until lightly golden.
  7. Once baked, remove from the oven and, using a sharp knife, score the surface of the shortbread into wedges. This will allow you to break it into wedges once it has cooled.
  8. Leave to cool for at least one hour.

Makes about 16 servings