Battenberg Cake

Ingredients
150g caster sugar
3 medium eggs, beaten
1 tsp vanilla extract
150g self-raising flour
2 tbsp milk
1 drop red food colouring
4 tbsp apricot jam
150g unsalted butter, softened
Marzipan
75g icing sugar, plus extra for rolling out
1 medium egg
1 tbsp lemon juice
175g ground almonds
1 medium egg yolk

Method
Preheat the oven to 180°C, gas mark 4. Butter a 20cm square cake tin and line the base with greased baking parchment. Divide the tin in half with a 30cm strip of foil folded into a double thickness

For the cake, beat together the butter, sugar, eggs, vanilla, flour and milk until smooth. Divide into 2. Use the tiniest dab of red food colouring to tint half the mixture pink. Spoon this into one side of the tin and spread level; fill the other side with the rest. Bake for 25–30 minutes. Cool for 5 minutes, then turn out onto a cooling rack.

Meanwhile make the marzipan. In a heatproof bowl over a pan of simmering water, whisk the sugars, egg and yolk for about 10 minutes until pale and thick. Take off the heat; mix in the lemon juice and ground almonds until smooth. Wrap and chill for 30 minutes

To assemble, lay one piece of cake on top of the other and trim to the same size. Cut in half lengthways to give 2 long strips of each colour. Warm the apricot jam and sieve. Lay a strip of pink cake on a board and brush the top and sides with jam; lay a plain strip next to it and do the same. Arrange the other 2 strips on top, colours reversed, and brush the jam all over. Roll the marzipan into a 20cm x 30 cm rectangle. Place the cake at one end of the rectangle and tightly wrap in the marzipan, patching any holes. Sit on the seam, slice and serve.