Heat the oven to 180°C/gas mark 4.
Butter, and line the bases of 2 18cm sandwich tins with baking parchment.
Beat the butter, sugar, flour, and eggs together in a large bowl using an electric whisk until it is lump free.
Divide the mixture between two bowls, then beat half of the jam and food colouring into 1 bowl, and all the vanilla into the other.
Spoon alternating dollops of the mixtures into the prepared 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.
Bake for 20-25 minutes, until golden a skewer inserted into the centres of the cakes comes out clean.
Leave the cakes to cool in the tins for 10 minutes, then turn out onto a wire rack to cool completely.
Place 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.
Sandwich the cakes together with the remaining raspberry jam and the White chocolate mixture, then generously dust the top with icing sugar.
Slice, then serve.
10 servings