Preheat the oven to 160°C/fan 140°C/gas mark 3. Grease an 18cm square cake tin and line with baking parchment. Tie a folded piece of baking parchment around the outside of the tin to protect against the heat.
Place the mixed fruit and brandy in a large pan and heat gently for 4 minutes. Transfer to a bowl and leave to cool. Add the ginger, chopped almonds and lemon and orange zest.
Sift the flour, mixed spice, cinnamon and ½ tsp salt into another bowl. In a separate large bowl, whisk together the sugar and butter until fluffy, then gradually beat in the eggs until combined. Fold in the flour and spice mixture and the ground almonds, then fold in the soaked fruit and nut mixture.
Spoon into the prepared tin and level. Bake for 2½ to 3 hours, until a skewer inserted into the middle comes out clean. Cover with foil for the last part of the cooking time if it’s getting too dark. Leave to cool in the tin for a few minutes, then transfer to a cooling rack.
Brush the cake with the glaze. Dust your work surface with the icing sugar and roll out the marzipan to ½cm thick. Lay over the cake, trim, then brush with boiled, cooled water. Roll out the icing to 1cm thick, then lay over the cake and trim.
Cut 3 stars from the icing trimmings with a large cookie cutter. Remove the centres with a smaller star cutter and set aside. Stick the outlines on the cake with warm water. Decorate the cake to your taste.