Add the butter, sugar, dried fruit, zezt & juice of a lime and an orange, as well as the rum to a large saucepan. Simmer over gentle heat for about 10 -12 mins and then allow to cool completely.
While the fruit-mix cools, grease and line two 8" x 4" baking tins.
Add the cooled fruit concoction to a large mixing bowl; sift in the flour, ground almonds, ground cinnamon, cloves, nutmeg and backing powder. Stir with a wooden spoon or spatula until well combined. Its going to be a fairly wet mix.
Add 4 well beaten eggs to the flour mixture and fold them in till well incorporated. Make sure to scrape the sides and bottom of the bowl as you go along so that batter is uniformly mixed!
Gently fold in the chopped walnuts.
Pre-heat the oven to 140°C. Pour the batter into the greased and lined baking tins, making sure to fill them up only to 90% of their full capacity.
Bake the cakes at 140°C for 40 mins and then poke with a skewer to check if done. If a skewer poked right into the middle comes out clean, you know your cakes are done! If not bake for an added 5 mins at a time.
Allow the cakes to cool in their tins for about 20 mins. While they are still warm, run a knife around the edges of the tin; this will help the cakes release easily later on.
Flip the cooled cakes out onto a chopping board; peel way the wrapper/ parchment paper, slice and serve!