Preheat oven to 160°C/320°F or 140°C (fan forced / convection).
Grease and line a 31.5 x 23.5 cm / 9 x 13" baking tray with baking paper on the bottom and overhang from the sides. The overhang will help in easily taking out the shortbread cookies later.
Place the softened butter in a medium sized bowl. Beat butter until pale and creamy. Sift over the icing sugar (powdered sugar) and combine together.
Add the flour in two portions. First mix one cup of flour, and then add the other. Beat until the dough comes together. Use your hands to turn the dough into a smooth ball of dough. Don't knead.
Bake for 25 – 30 minutes, turning the tray halfway through the baking process, until the shortbread is light golden. Place the baking tray on a cooling rack to cool completely. This recipe makes about 22 - 24 cookies. Nutrition yield is for a serving of 1 cookie per person.
Note: The shortbread recipe is based on the recipe for shortbread cookies on Recipe Tin Eats.