Two-tone Sponge Slices

For the cake: heat the oven to 180°C (160° fan) 350°F gas 4. Grease 2 x 22cm x 8cm|9" x 3" loaf tins and line the bases with non-stick baking paper.

Divide the butter and sugar between 2 bowls, and beat well until light. Beat 3 eggs into each bowl.

Stir the vanilla and half the milk into 1 bowl, then fold in 175g|1 1/2 cups flour.

Fold the remaining flour, almonds, cocoa and remaining milk into the other bowl. Mix well until blended.

Spoon into the tins and bake both for 30–40 minutes. Cool in the tins for 10 minutes, then place on a wire rack to cool completely.

Place one cake on top of the other and trim off the crusty edges so they are both the same size. Cut the cakes in half lengthways to make 4 long rectangles.

Brush the long side of one of the cakes with jam and sandwich together with a cake of a contrasting colour. Repeat the process with the other 2 cake rectangles, brushing all the edges with jam. Trim the cake so the sides are straight, if necessary.

Knead the marzipan until softened. Knead in the cocoa powder until evenly coloured

Roll out the marzipan on a surface dusted with icing sugar into a rectangle of about 35cm x 24cm|14" x 10"; large enough to wrap the cake completely, leaving the ends exposed. Turn the cake upside down on the marzipan and brush the underside of the cake with jam.