Pre-heat the oven to 150ºC and grease a small, round pan (I used a 6" spring-form but you could pretty much use any size and then adjust the baking time).
Beat the butter and sugar together until light and fluffy. Combine the flours and stir into the butter/sugar, mixing until a dough pulls together. Scrape the last bits together with your hands.
Press the dough into the prepared pan, pushing it up to the edges. Take the back of a spoon and smooth the top until it is even. Decorate by pushing a fork, or something else, into the dough. Score lines into the dough almost all the way down and then sprinkle with a little sugar.
Bake for around 30-35 minutes, just until the edges are browning but the rest still looks pale. Cool for ten minutes or so, then cut through the scores you made before baking. Allow the shortbread to cool completely before moving them. Enjoy!