― 1 store-bought sponge cake or 1 quantity basic sponge cake, see recipe 3 cups (480g) icing (confectioner’s) sugar ¾ cup (75g) cocoa powder ⅓ cup (80ml) boiling water 75g butter, melted dessicated coconut, to coat ∙ Make 1 quantity basic sponge cake in an 18cm-square cake tin and cool on a wire rack. ∙ Cut into 6cm squares. ∙ Sift together the icing sugar and cocoa. ∙ Mix with the boiling water and melted butter. ∙ Using 2 forks to hold the sponge squares, [...].