1.Combine fruit and rum in medium bowl. Cover; stand overnight.
2.Line 20cm x 30cm lamington pan with baking paper, extending paper 3cm over long sides of pan.
3.Beat butter, sugar and eggs in small bowl with electric mixer until pale in colour (mixture will curdle, but will come together later). Add butter mixture to fruit mixture; stir in nuts, chocolate and sifted flour and soda. Spread mixture in pan.
4.Roll out marzipan on icing-sugared surface to 20cm x 30cm rectangle; place in pan over dark cake layer.
5.Preheat oven to 150°C (130°C fan-forced).
6.To make light layer; beat butter, sugar and eggs in small bowl with electric mixer until pale in colour (mixture will curdle, but will come together later). Stir in sifted flour, rum, fruit and nuts. Spread mixture evenly over marzipan.
7.Bake cake about 1 hour. Cover with foil; bake further 1 hour. Brush cake top with extra rum. Cover with foil; cool in pan.
You need only slender small servings of this ultra-rich cake, which is why we’ve chosen to bake it in a lamington pan. The layer of marzipan in the middle keeps the cake moist as well as adding to the flavour. Buy the best marzipan (or almond paste) you can find.