Hi C - follow the recipe you have for the cake and top with 2 tablespoons demerara sugar with a pinch of cinnamon to get a crunchy finish.
In case you lost the cake recipe try this:
450g (1lb) Mixed Dried Fruit
255g (9oz) Self Raising Flour
235ml (8floz) Cider
170g (6oz) Brown Sugar
110g (4oz) Butter
2 Large Eggs
1 tsp Mixed Spice
Place the dried fruit, cider, sugar, butter and mixed spice into a saucepan.
Bring to the boil, stirring well.
Allow to cool completely.
Add the beaten eggs and flour to the mixture, mixing thoroughly.
Pre-heat oven to 180�C: 350�F: Gas 4.
Line a 20cm (8 inch) cake tin with buttered greaseproof paper.
Bake in the centre of the oven for 1 hour 20 minutes or until the cake is easily pierced with the tip of a knife.
(from The Foody.com)