Preheat the oven to 180C/350F/gas mark 4
Use two Swiss Roll Trays
Grease the Swiss Roll trays. Heat gently together the syrup, sugar and butter until the sugar has dissolved and the butter melted. Take off the heat and stir in the spices. Set aside to cool.
Sift the flour with the salt and baking powder twice, then into a bowl. Stir in the melted ingredients, and add the lemon and orange rind and sour cream. Combine well. Add the candied peels, fruits, and nuts, and finally the orange juice. Pour the mixture into the two prepared trays. They should be about half full, as the mixture rises well in baking. Bake in the preheated oven for 35 - 40 minutes. Remove and allow to cool in the trays for ten minutes, before turning out onto a wire rack.
Filling: Split each cake in half when cool. Spread a quarter of the apricot jam over the bottom layer and cover with a layer of cake. Roll the marzipan on a sheet of greaseproof paper dredged with icing sugar until it is large enough to fit the cake. Brush the cake first with more apricot jam, then sandwich the marzipan with it. Cover with another layer of cake which has first been coated with apricot jam, and brush the top of this with the jam too. Cover with the last piece of cake. Ice the whole of the cake with carob icing and decorate with a few split almonds.
Carob Icing: Sift icing sugar and carob powder into a bowl, stir in the combined butter and water. Beat until smooth.
