Coconut lamingtons

Heat the oven to 180C/fan 160C/gas 4 and line the base and sides of a rectangular 20 x 30cm cake tin with baking paper. Put the butter, sugar, flour, baking powder, custard powder, 3 tbsp cornflour, xanthan gum, eggs, advocaat and vanilla into a food processor and whizz to a smooth batter or using electric beaters in a large bowl. Pour the batter into the tin and smooth the top, then bake for 22-25 minutes or until a skewer poked into the middle of the sponge comes out clean. Cool in the tin for 10 minutes, then turn out onto a sheet of baking paper that’s been lightly greased with coconut oil – so the cake cools upside down.

While the cake bakes, mix a little of the custard into the remaining 1 tbsp of cornflour to make a smooth paste in a small saucepan. Gradually stir in the rest of the custard, then heat gently, stirring constantly, until it thickens to the consistency of softly whipped cream.

Once the cake is completely cool, turn the right way up and halve into two 20 x 15cm pieces – use a ruler – accuracy is important if you want neat lamingtons at the end! Use a skewer to poke holes all over both sides (but don’t push the skewer all the way through) – this helps the filling settle. Spread the custard over one half of the sponge, then gently sandwich the other on top so the outsides of the sandwich are exposed.

Trim any brown edges to neaten until you have an 18 x 12cm cake. Cut this into 6 x 6cm square mini cakes.

Put the white chocolate and coconut oil in a heatproof bowl over a pan of water. Heat gently until the chocolate has melted, then stir to incorporate the oil. Spread the desiccated coconut over a tray. Use a pastry brush to paint the sides of each lamington with the melted chocolate, then roll in the coconut to coat. Sit on a wire rack to set, and repeat with the other 5 cakes. Once the white chocolate is firm-ish again, they’re ready to demolish.