Photo: Kate Gibbs
Use both chocolate and cocoa for the icing. Chocolate makes it thick and creamy, and gives the lamingtons an "iced" quality, while the cocoa soaks into the cake.
½ cup self-raising flour
½ cup plain flour
½ cup cornflour
6 large eggs, at room temperature
¾ cup sugar
¼ tsp salt
1 tsp vanilla extract
75g unsalted butter, melted, at room temperature
170g dark (70 per cent) chocolate
40g unsalted butter
¾ cup milk
2 cups pure icing sugar
2 tbsp Dutch cocoa
3 cups desiccated coconut
Grease a 23cm-square cake tin and line bottom with baking paper. Preheat oven to 170ºC (fan-forced).
Sieve flours together in a bowl, then sieve again. Set aside.
In bowl of an electric beater, whisk eggs until frothy, add sugar and salt and beat on high speed for 8-10 minutes, until very thick. A thick ribbon should form when you lift beaters or whisk out of bowl. Fold in vanilla extract.
Sieve flours one more time, straight into egg mixture. Fold together using a hand whisk. When completely combined, fold in melted butter. Do not over mix.
Pour batter into prepared tin – use a spatula to scrape the bowl. Bake for 25-30 minutes, until cake pulls away from tin at sides and a skewer inserted into middle comes out clean. Cool a bit in tin, then turn cake out onto a wire rack, cover with a tea towel and set aside (overnight, if desired).
For chocolate icing, combine chocolate, butter and milk in a medium bowl and set over a saucepan of boiling water. Stir until melted, then remove from heat and stir in icing sugar and cocoa until smooth.
Use a long serrated knife to cut crusts from sides of cake, then cut in half horizontally. Dollop spoonfuls of chocolate mixture on bottom half of cake, spread evenly with a small spatula, then sandwich with other half of cake. Cut cake into 16 squares.
Add 3 tbsp boiling water to chocolate mixture, stir well. Pour coconut into a wide bowl. In batches of two, use your hands or two forks to dip lamingtons into chocolate, coating on all sides, then transfer to coconut. Roll to coat and transfer to a wire rack to set.