I blogged some time ago about the sponge I made to make lamingtons, and then failed to mention the result:
The lamingstons were made for my birthday afternoon tea. They went very quickly.
From Stephanie Alexander, The Cook’s Companion:
Cut day-old genoese sponge into 5 cm cubes and refrigerate. Mix 1 part cocoa with 8 parts icing sugar, 1 part boiling water and 1 part melted butter to make icing and prepare a tray of dessicated coconut. Impale a square of sponge on a fork and dip in icing, then in coconut. Allow to dry on a wire rack before storing in airtight tins.
(Or eat immediately 🙂