1. Heat the oven to 180C (160C fan).
2. In a large bowl, sift together the flour, baking powder, baking soda and mixed spice. Add the diced butter and rub it in until the mixture resembles the fine breadcrumbs. Stir in the Dark Muscovado sugar, mixed fruit and milk. Using a wooden spoon, mix it all together until fully combined. Spoon the mixture into prepared 23 cm bundt tin (well oiled and dusted with flour). Bake for about 1 hour or until the toothpick inserted in the middle comes out clean. Cover the cake with some foil for the last 15 minutes of baking if necessary.
3. To make the syrup, combine the rum and Caster sugar in a small saucepan over low heat and allow sugar to dissolve. Set aside to cool.
4. Prick the hot cake with the cocktail stick and brush with roughly half of the rum syrup. Leave the cake to cool in the tin for 10 minutes, then take it out onto a wire rack. Brush with the remaining rum syrup and leave for another 10 minutes.
5. Make the icing by mixing the icing sugar and rum then pour it on top of the cake. Decorate the cake with some fruit and enjoy!
Before adding dried fruit into your fruit cake batter, coat them with flour to help keep them from sinking to the bottom of the pan.