Ingredients

• 25g (1 1/2 cups) plain flour
• 1 teaspoon baking powder
• Pinch of salt
• 6 eggs, at room temperature
• 155g (3/4 cup) caster sugar
• 1 teaspoon vanilla extract
• 50g unsalted butter, melted
• 2 tablespoons warm water
• 250g mascarpone
• 75g (1/2 cup) pure icing sugar
• 60ml (1/4 cup) thickened cream
• 130g (1 1/2 cups) moist coconut flakes

Coffee icing

• 500g pure icing sugar
• 1/2 teaspoon coffee powder
• 80ml (1/3 cup) Kahlua liqueur
• 20g unsalted butter, melted

Method

• Step 1 Preheat oven to 180°C/160°C fan forced. Grease a 20 x 30cm lamington pan. Line with baking paper, allowing 2 long sides to overhang.
• Step 2 Sift flour and baking powder into a bowl. Add salt. Use electric beaters to beat the eggs, sugar and vanilla in a large bowl for 8 minutes or until thick and pale. Sift one-third of flour mixture over the egg mixture. Fold until combined. Repeat with the remaining flour mixture, in 2 batches.
• Step 3 Pour butter and water around the edge of the bowl. Fold to combine. Pour into prepared lamington pan. Bake for 25 minutes or until mixture springs back when lightly touched. Cool slightly in pan for 5 minutes. Turn onto a wire rack and allow to cool completely. Halve whole cake horizontally. Trim edges of the cake.
• Step 4 Beat mascarpone, icing sugar and thickened cream until fluffy. Spread over base. Top with remaining base.
• Step 5 For coffee icing, sift icing sugar and coffee powder into a heatproof bowl. Add Kahlua and butter and stir until smooth. Place over a saucepan of warm water.
• Step 6 Cut cake into 15 squares. Place coconut on a plate. Use 2 forks to dip 1 cake square in icing. Shake off excess. Roll in coconut to coat. Transfer lamington to a lined tray. Repeat with remaining cake, icing and coconut. Set aside for 1 hour to set.