Put the sultanas, raisins, glacéé cherries, currants, peel, figs, apricots and prunes in a large bowl and pour over the brandy, orange zest and juice. Mix well, cover and leave to stand overnight.
Line the base of a 23cm/9in cake tin with a double thickness of parchment paper. Line the sides of the tin with a double thickness of parchment paper, so that it comes 4-5cm/1½-2in above the edge of the tin. Wrap a sheet of folded newspaper around the outside of the tin and secure with string. Stand the prepared tin on a folded sheet of newspaper on a baking sheet. Preheat the oven to 150C/300F/Gas 2.
In a large bowl, beat the butter and sugar together until pale and fluffy. Gradually beat in the eggs, adding a little of the flour if the mixture starts to curdle. Add the fruit, its soaking liquid and the nuts and mix well. Stir in the flour, taking care not to over mix it. Spoon the mixture into the prepared tin and level the surface with the back of a spoon. Bake for 3-4 hours or until a skewer inserted into the centre comes out clean. If the top of the cake starts to get too brown, cover with a sheet of baking parchment.
When the cake is cooked, remove it from the oven and leave to cool completely in the tin. Store the cake in an airtight tin, wrapped in greaseproof paper and foil for between two and three months. Feed the cake with brandy every 2-3 weeks until you are ready to decorate it.
Pass the jam through a sieve and warm it in a pan with 1 tbsp of water. Invert the cake onto a serving plate or board. Use a little of the marzipan to fill any gaps between the cake and the plate. Brush the jam all over the cake. Roll out the remaining marzipan and lift carefully onto the cake, easing it around the sides. Trim off any excess with a sharp knife.
Roll out the ready-to-roll icing to a 0.5cm/¼in thickness and cut out as many star shapes as you can, re-rolling the trimmings. Set aside on parchment paper to harden. Meanwhile, make up the royal icing according to the instructions on the packet. Spread the icing over the cake to cover it, then roughly peak it using a spatula. Arrange the stars on top and scatter over the silver balls. Leave the icing to harden, then dust the cake with icing sugar.
