Place the sultanas, raisins, candied peel, dates, apricots, dried currants, and the crystallized ginger in a bowl. Pour on the brandy or whiskey and allow to soak for at least 2 hours.
Preheat the oven to 300 degrees F/150 degrees C/Gas mark 2. Line the cake tin with greaseproof paper and wrap a collar of brown paper around the outside, which will help prevent the cake from drying out.
Cream the butter in a large bowl or in an electric food mixer until soft. Add the sugar and beat until the mixture is light and fluffy. Add the eggs, one at a time, beating well between each addition. Stir in the orange zest and ground almonds, then sift in the flour and mixed spice, cinnamon, and nutmeg and fold in gently. Fold in the dried fruit and any brandy or whiskey left in the bowl.
Transfer the mixture to the prepared cake tin. Bake in the oven for 2 1/2 to 3 1/4 hours (a round tin will take longer), until a skewer inserted into the middle of the cake comes out clean.
Cover the cake, still in the tin, with foil and allow to cool. Once the cake has cooled, remove it from the tin and cover again in foil until you are ready to cover it with almond paste.
To coat in almond paste: Preheat the oven to 425 degrees F/220 degrees C/Gas mark 7.
To make the almond paste: Mix the ground almonds and sugar together in a bowl. In another bowl, beat the egg, add the brandy or whiskey and the almond essence, then add to the dry ingredients and mix to a stiff paste; you may not need all the egg. Sprinkle the work surface with icing sugar (confectioners'), turn the almond paste out onto the surface and gently knead until smooth.
Remove the foil and greaseproof paper from the cake. Take about 1/2 of the almond paste and place it on a work surface that has been dusted with icing sugar (confectioners'). Roll out until it is about 1/2-inch/1 cm thick. Brush the top of the cake with the lightly beaten egg white and turn the cake upside down onto the almond paste. Cut around the edge of the cake, then carefully turn the cake the right side up with the lid of almond paste attached to the top.
Next, measure the circumference of the cake with a piece of string. Roll out 2 long strips of almond paste and trim both edges to the height of the cake with a palette knife. Brush the cake and the almond paste lightly with egg white and press the strip against the sides of the cake. Do not overlap or there will be a bulge. Use a straight-sided water glass to even the edges and smooth the join, and rub the cake well with your hand to ensure a nice flat surface.
At this stage, carefully place the cake on a large, oiled baking tray. Roll out the remainder of the almond paste approximately 1/4-inch/5 mm-thick and, using festive cutters, cut out star, heart, holly or Santa shapes. Brush the whole surface of the cake with the beaten egg yolks and stick
the shapes on top and around the sides, if you wish. Brush the cut outs with egg yolk as well.
Bake the cake in the oven for 10 to 20 minutes (not too near the top of the oven) until it is golden and toasted. Remove the cake from the oven, allow to cool, then transfer to a serving plate.
For Candied Peel:
Cut the fruit in 1/2 and squeeze out the juice. (Reserve the juice for another use, perhaps home-made lemonade.) Put the peel into a large bowl, add the salt and cover with cold water. Leave to soak for 24 hours.
Next day, throw away the soaking water; put the peel in a large saucepan and cover with fresh cold water. Bring to the boil, cover and simmer very gently for about 3 hours or until the peel is soft.
Cook's Note: It should mash between the tips of your fingers easily when it is cooked.
Remove the peel from the pan and discard the water. Scrape out any remaining flesh and membrane from inside the cut fruit, using a teaspoon, leaving the white pith and rind intact.
In a clean large saucepan, dissolve the sugar in 1 3/4-pints/1-litre water, then bring to the boil, stirring to dissolve the sugar. Add the peel and simmer gently for 30 to 60 minutes until it looks translucent (shiny and 'candied') and the syrup forms a thread when the last drop falls off a metal spoon. Remove from the heat and allow to stand for 20 to 30 minutes to slightly cool.
Put the candied peel into sterilized glass jars* and pour the syrup over. Cover and store in a cold place or in the refrigerator. It should keep, stored like this, for at least 3 months.
To sterilize jars for jams and preserves, wash them in hot soapy water, then rinse and dry. Place the jars upturned on a baking tray in a warm oven preheated to at least 250 degrees F/120 degrees C, Gas mark 1/2 for approximately 15 minutes until completely dry. Leave them upturned on a clean tea towel until ready to use. Alternatively, you can put them through a hot cycle in the dishwasher.
For American Frosting:
Ensure your cake is ready before you start, as this icing begins to set very quickly. Bring to the boil a saucepan of water large enough to hold a heatproof bowl. Place the egg whites in the bowl and whisk with a hand-held electric beater until very stiff.
In a separate saucepan over a medium-high heat, dissolve the sugar in the water and boil for 5 to 10 minutes until the liquid is thick and syrupy and has reached the 'thread' stage - when the last few drops that fall from a metal spoon dipped into the syrup come off in one long, quite thick and syrupy thread.
Pour the boiling syrup over the stiffly beaten egg whites, whisking all the time with the hand-held beater. Place the bowl in the saucepan of simmering water. Continue to whisk over the water for 10 to 15 minutes until the icing is snow white, very thick and meringue-like.
Spread quickly over the cake with a palette knife, regularly dipping the knife into a jug of boiling water. The icing sets very quickly at this stage, so speed is essential.