Step 1

Preheat oven to 180°C/350°F. Grease two deep 20cm (8-inch) square cake pans. Line bases with baking paper.

Step 2

Beat egg whites and sugar in medium bowl with electric mixer about 8 minutes or until sugar is dissolved. Beat in egg yolks, one at a time. Fold triple-sifted cornflour, custard powder and baking powder into egg mixture.

Step 3

Divide mixture evenly between prepared pans. Bake sponges about 25 minutes. Turn sponges, top-side up, onto baking-paper covered wire racks to cool.

Step 4

Make chocolate icing. Sift icing sugar and cocoa into large heatproof bowl, stir in butter and milk. Stir over large saucepan of simmering water until icing is of a coating consistency.

Step 5

Pour icing into shallow tray, sprinkle half the coconut over separate shallow tray. Quickly dip base and sides of one cake in icing (leave top uniced), press coconut onto cake. Place cake, uniced-side down, on baking paper-lined tray. Repeat with remaining cake, icing and coconut. Refrigerate cakes about 1 hour or until firm.

Step 6

Make silky butter cream. Have butter at room temperature. Stir sugar, the water and milk in small saucepan over high heat, without boiling, until sugar dissolves.

Step 7

Sprinkle gelatine over milk mixture, stir until gelatine dissolves. Cool. Beat butter in small bowl with electric mixer until as white as possible. Gradually beat in extract and milk mixture until light and fluffy.

Step 8

Split one cake in half. Place one layer, icing-side down, on serving plate. Top with one-third of the butter cream then second cake layer. Spread with another one-third of the butter cream.

Step 9

Split remaining cake in half, top butter cream with un-iced cake layer. Spread with remaining butter cream, top with remaining iced cake layer, icing-side up.