Although I don’t really make sponge cakes that often, this is one of my favourites, and it always seems to be popular. And don’t be put off by the photo, admittedly it isn’t my best work. Having said that, the cake is never going to be a showstopper, at least appearance wise, but that isn’t really the point here, this is a comforting, old fashioned sponge sandwich. The cake itself is two really moist coconut sponge cakes, sandwiched with a coconut buttercream and topped with coconut flavoured royal icing, and is taken from Nigella Lawson’s How To Be a Domestic Goddess. The coconut flavour in the icing comes from Malibu, or coconut flavoured white rum, and as Nigella notes in her own introduction to this recipe, Malibu is quite useful for cooking with since good coconut flavouring can be quite hard to come by. If making two different types of icing seems like a bit of a faff, then I would recommend tripling the recipe for the coconut buttercream, using a third to sandwich the sponges, and the other two thirds to cover both top and sides. If you wish, you could also add a smearing of good cherry jam inside too.
From Nigella Lawson’s How To Be a Domestic Goddess
For the cake
225g unsalted butter, softened
225g caster sugar
1/2 teaspoon pure vanilla extract
200g self-raising flour
1/2 teaspoon baking powder
50g desiccated coconut, soaked in 150ml boiling water
For the coconut buttercream
25g dessicated coconut
75g soft unsalted butter
150g icing sugar, sieved
1 tablespoon Malibu
For the icing on top
2-4 tablespoons Malibu
125g instant royal icing (which may be labelled ‘royal icing sugar’)
Preheat the oven to 180C / 160C fan and butter and line two 20cm sandwich tins. As always, make sure all of your ingredients are at room temperature before starting. Boil the kettle, put 50g of desiccated coconut into a small bowl or jug, and pour over 150ml of boiling water. Leave this to stand and let the coconut soak up the water.
Cream together the butter and sugar until light and fluffy, then add the eggs, one at a time, with a spoonful of the flour between each, beating in well. Then beat in the vanilla. Add the remaining flour, cornflour and baking power, and fold until all is combined. Finally, give the coconut a stir in its boiling water and then tip the whole lot into the batter. (If you wish, the original recipe does say you can whizz everything bar the coconut and water in the processor until you have a smooth batter, whizzing in the coconut at the end, but here I think the slightly longer way gives a better result.)
Pour the batter into the prepared tins, and cook for 25-30 minutes. (The original recipes says 25, I found mine needed 30, although check a 25 – a cocktail stick or cake tester should come out more or less clean.) Leave to cool in their tins for ten minutes, before turning them out onto a wire rack to cool fully.
While the cakes are cooking, toast the 25g coconut for the buttercream in a dry pan, shaking it now and then, until it is nicely golden and smells delicious. Tip it onto a plate to stop it toasting further, and allow it to get completely cold before you make the buttercream. Keep watching it – it will turn from nicely toasted to black in not much time at all.
To make the buttercream, cream together the butter and icing sugar. When you have a smooth paste, beat in the Malibu and then the cold toasted coconut. Spread onto the bottom cake, to about 2cm from the edge to allow for splurging, and then place the other cake on top, pushing down gently.
For the royal icing, add two tablespoons Malibu to the instant royal icing (basically following the liquid-to-sugar ration from the packet) and whisk (preferably with the aid of machinery) until smooth and just runny enough to coat the cake. You may need the other 1 or 2 tablespoons of Malibu to achieve this – I did. Pour the icing onto the centre of the cake, and allow it to spread out, helping it along the way with a silicone spatula if needed. Let the icing set before serving the cake.