A traditional Aussie favourite!
Preheat oven to 180'C. Line a 20cm x 30cm lamington tray with greaseproof paper.
Sift together the flours and set aside.
Using an electric mixer, beat the eggs and sugar until fluffy and doubled in size. Gently mix through the flour making sure it's well incorporated.
Pour the butter in slowly and fold carefully through.
Pour mixture into the prepared tin and bake for 18-20 minutes, until soft and spongy to touch. Leave to cool in tin for 10 minutes. Transfer to a cooling rack. Cut sponge into 5 cm cubes.
Stir together the cocoa, icing sugar and butter. Add enough boiling water to make a runny icing. Place the coconut in a tray. Pierce the sponge cubes with a fork and dip into the chocolate icing. Dip sponge in the coconut. Place onto greaseproof paper and leave to dry.