Method

• 1.
  Preheat oven to 170°C/150°C fan-forced. Grease a 20cm x 30cm lamington pan and line the base and sides with baking paper, extending 2cm along the two long sides. Line a wire rack with baking paper.
• 2.
  Sift the flours into a medium bowl. Place eggs in the bowl of a stand mixer fitted with the whisk attachment. Whisk on medium-high speed for 5 minutes or until thick and tripled in volume. Gradually add sugar, whisking constantly, then whisk for 8 minutes until sugar has dissolved. Using a metal spoon, fold in the flour mixture in 2 batches, folding all the way to the bottom of the bowl to pick up any pockets of flour, then fold in butter and vanilla. Pour into prepared pan, level surface and bake for 40-45 minutes until a skewer inserted into the centre comes out clean. Cool in pan for 5 minutes, then turn onto lined wire rack, peel away baking paper and discard and cool completely.
• 3.
  Trim all four edges of the sponge by 5mm, then the top by 3mm. Cut sponge into 15 even squares. Place on a baking paper lined baking tray.
• 4.
  For the coating, place icing sugar, cocoa, butter and boiling water in a large heatproof bowl and whisk until smooth. Working with one lamington at a time and using two forks, lightly dip sponge squares in the icing, allowing excess to drip off, then coat in coconut. Pressing with your hands to help adhere. Return to tray and chill for 30 minutes to set before assembling.
• 5.
  In the cleaned bowl of a stand mixer fitted with the whisk attachment, whisk cream and extra vanilla on medium-high speed to stiff peaks. Set aside.
• 6.
  Using a small serrated knife, cut each lamington horizontally about 1.5cm from top. You want the top piece to be one-third thickness of the base, this helps to prevent the cream oozing out once assembled. Spread the cut bases with jam, then dollop or pipe on the cream and return tops. Serve. Lamingtons are best eaten on the day they are made.