Preheat oven to 150 degrees C. Line the base and side of a 23cm cake tin with a double layer of baking paper.
Cream butter and sugar in a large mixing bowl. Add eggs one at a time; beat well after each addition. (The mixture will curdle a little at this point because of the unusually high proportion of eggs to other ingredients in this recipe. It will come together when the dry ingredients are added.)
Fold in the ﬂour. Stir in dried fruit, glacé cherries, chopped peel, ground almonds and zests.
Spoon mixture into tin; smooth the top. Bake in the centre of the oven for 3 1/2 – 4 hours or until a skewer inserted in the centre of the cake comes out clean.
Remove the cake from the oven; leave to cool in tin for 1 hour.
Carefully turn cake out onto a wire rack and leave to cool completely. Do not remove the baking paper.
Wrap the cold cake, still in the baking paper, in cling wrap and wrap it again in foil. Place the cake in an airtight container and store in a cool, dry, airy cupboard until ready to ice it.
Remove cake from wrappings and place upside-down in the centre of a 30cm round gold or silver cake board, or on a cake stand, if preferred.
Using a fine skewer, make several holes in the base of the cake; insert the skewer to a depth of about 4cm. Spoon rum, whiskey or brandy over the base of the cake and allow it to gradually seep into the holes.
Roll out the almond paste to a neat round about 33cm in diameter. Turn cake right side up and brush all over with the warm, sieved apricot jam.
Carefully lift the paste onto the cake; smooth it evenly over the top and down the side, pressing it gently but ﬁrmly into position. Trim off any excess paste from the base. Smooth paste with a palette knife.
Leave cake, uncovered, in a cool, dry place for 24 hours to allow the paste to dry completely before adding the icing.
Spoon 3 tablespoons of the icing mixture onto the cake and spread it evenly over the top only. Using a clean, metal ruler, smooth the icing by pulling the ruler over the top of the cake. Trim the excess icing from around the edge of the cake and leave overnight to allow the icing to dry.
Put the remaining icing into a clean bowl, cover the surface closely with plastic wrap and refrigerate. Next day, beat the icing up again and give the top of the cake another coat, spreading it evenly and then smoothing with a ruler as before.
Spread the remaining icing around the side of the cake, letting a little overﬂow onto the top. Pull the icing up into attractive peaks and mark into swirls with a palette knife.
Allow the icing to dry once more overnight, then decorate with a traditional Christmas ornament of your choice.