Process all ingredients, except caster sugar, together in a food processor until mixture resembles fine breadcrumbs
Press mixture together until it forms a dough. Divide dough in two
Roll out dough between 2 sheets of baking paper until 5mm thick
Using a snowflake-shaped cutter, cut shapes from dough. Transfer to prepared trays. Sprinkle with caster sugar if desired. Bake at 160°C for 30 minutes or until dry and firm but still pale. Transfer to a wire rack to cool completely. Dust with icing sugar. Serve
Tips & Hints:
Makes: 20 biscuits. Shortbread will keep in an airtight container for up to 1 month.