Alternatively serve sprinkled with icing sugar or ice with cream cheese icing. Beat together, spread on cake and sprinkle with roasted chopped macadamia nuts and orange zest. For a gourmet-looking cake use 1 quantity of the recipe. Beat butter, sugar and vanilla in small bowl with electric mixer until pale and fluffy. Transfer mixture to large bowl, stir in sifted flours and nuts in two batches.
Press ingredients together.
Divide into two portions. Roll each portion between two sheets of baking paper into a 23cm circle. Press an upturned 22cm loose-based fluted flan tin into shortbread to cut rounds. Cut each round into 16 wedges. Stand for 10 minutes before transferring to a rack to cool.