01 - Preheat oven to 350°F. Grease an 8-inch square cake tin and line with parchment paper. Create a divider using foil and parchment to split the tin in half vertically.
02 - In a large bowl, beat softened butter and caster sugar until pale, light, and fluffy using an electric mixer.
03 - Beat in eggs one at a time, ensuring each egg is fully incorporated before adding the next. Mix well after each addition.
04 - Fold in self-raising flour, ground almonds, baking powder, vanilla extract, and almond extract until just combined. Do not overmix.
05 - Divide batter evenly between two bowls. Add pink food coloring to one bowl, a few drops at a time, mixing until a soft pink hue is achieved.
06 - Spoon pink batter into one side of the prepared tin and plain batter into the other side. Smooth tops with an offset spatula.
07 - Bake for 25 to 30 minutes until a skewer inserted into the center comes out clean. The cakes should be golden and spring back when touched.
08 - Let cakes cool in tin for 10 minutes, then carefully remove and transfer to a wire rack. Cool completely before assembling.
09 - Trim all edges from both sponges to create even rectangles. Cut each sponge in half lengthwise to create four equal long strips.
10 - Warm apricot jam in a small saucepan over low heat, then sieve through a fine-mesh strainer to remove any fruit chunks.
11 - Brush jam on the long sides of cake strips. Arrange in a 2x2 checkerboard pattern, alternating pink and plain sponges so each layer shows both colors.
12 - Dust work surface with icing sugar. Roll marzipan into a rectangle large enough to completely wrap around the assembled cake with overlap.
13 - Brush jam all over the outside of the assembled cake. Carefully wrap marzipan around the cake, sealing the seam underneath. Trim excess marzipan.
14 - Press marzipan gently to seal. Lightly score the top in a diagonal pattern with a sharp knife for decoration. Slice and serve.