Forget the cocktail – this mojito cake is a fabulous new version of a classic
For the genoise:
• oil, to grease
• 125g caster sugar, plus extra to dust
• 125g plain flour, plus extra to dust
• 55g butter
• 4 eggs, at room temperature
For the syrup:
• 100g sugar
• 100ml water
• 70ml rum
• 70ml lime juice
• large sprig fresh mint
For the frosting:
• 150g salted butter, softened
• 250g icing sugar
• 1 tablespoon milk
• 1 lime
• 1-1 1/2 tablespoons rum
• 1 egg white
• handful small mint sprigs
• caster sugar, to dust
1 Heat the oven to 180°C, lightly oil the cake tin and line the base with a disc of greaseproof paper. Dust with sugar and then flour. Make the genoise sponge.
2 To make the syrup, dissolve the sugar in the water in a heavy-based pan, using the handle of a wooden spoon to agitate the sugar so it does not ‘cake’ on the base of the pan.
3 When all the sugar has dissolved, boil the syrup for 2–3 minutes, then add the rum and lime juice. Lightly bruise the mint, add to the syrup and leave to infuse for 10–15 minutes.
4 Taste and adjust the flavour as necessary: there should be a balance between sugar, lime, rum and mint, with none of the flavours particularly dominant.
5 To make the frosting, beat the butter in a medium bowl with a hand-held electric whisk until smooth. Add half the icing sugar and continue to beat until smooth. Add the remaining icing sugar with the milk and beat until light, creamy and smooth.
6 Finely grate the lime zest and squeeze the juice. Add the rum, lime juice and zest to the frosting, to taste.
7 To assemble, cut the cake in half horizontally. Remove the mint from the syrup and, using a teaspoon, drizzle the syrup over both cut sides of the cake, letting it soak in gently.
8 The syrup should moisten and flavour the cake rather than saturate it, so you may not need to use it all.
9 Lightly beat the egg white for the decoration, and use to brush the mint sprigs. Dust with caster sugar and set aside.
10 Use half the frosting to sandwich the 2 cake layers together. Spread the remaining frosting over the top of the cake as evenly as possible and scatter the mint sprigs on top to decorate.