Preheat the oven to 180º C. Grease and line 1 x 23cm round cake tin or three smaller ones as specified above.
Spread the nuts out onto a baking sheet and roast for about 10 minutes. Wrap in tinfoil to keep warm.
Place the citrus peel, dried fruit and zest in a large mixing bowl.
Combine the flour, cocoa, all the spices and salt in a bowl. Sift the dry ingredients directly over the fruit mixture and work through by hand.
Melt the chocolate over a double boiler.
Place the castor sugar and honey in saucepan over a low heat and stir continuously until it starts to boil. Once the sugar has dissolved, stop stirring and simmer until the mixture reaches 114º C on a sugar thermometer.
Pour the hot syrup over the fruit and flour, followed by the melted chocolate and the warm nuts. Mix together with a wooden spoon while still warm. It becomes more difficult as it cools. Divide the mixture between the tins and press down firmly.
Bake at 180º C for approximately 15 minutes.
Cool completely in the tins. Dust with icing sugar and wrap in cling film and then parchment paper.