For the white chocolate layer
- STEP 1
Heat the oven to 180C/160C fan/gas 4. Butter and line the bases of two 18cm sandwich tins. Beat the butter, sugar, flour and eggs together in a large bowl using an electric whisk until it's lump-free.
- STEP 2
Divide the mixture between two bowls. Beat half the jam and the food colouring, if using, into one, and beat the vanilla into the other.
- STEP 3
Spoon alternating dollops of the mixes into the prepared cake tins, then swirl together using a skewer. Do this carefully – if you overdo it, you won’t see the pattern. Smooth the tops with the back of a spoon.
- STEP 4
Bake for 20-25 mins until golden and a skewer inserted into the centre comes out clean. Leave to cool in the tins for 10 mins, then turn out.
- STEP 5
Meanwhile, to make the white chocolate layer, put the chocolate and cream in a heatproof bowl set over a pan of just simmering water, ensuring the bowl doesn’t touch the water. Stir until the chocolate has melted into the cream and you’re left with a smooth, glossy mixture. Leave to cool completely in the fridge, stirring occasionally.
- STEP 6
Sandwich the cakes together with the remaining raspberry jam and the white chocolate mixture, then generously dust the top with icing sugar. Slice and serve.