Put the raisins and cranberries in a small heavy-based saucepan with the wine, redcurrant jelly and spices. Heat until the jelly dissolves, then bring to the boil and boil for 2–3 minutes until the syrup is reduced by about half. Allow to cool.
Mix the nuts and chocolate in a bowl with the flour, orange rind, butter, egg and fruit mixture to make a paste. Place teaspoons of the mixture, spaced slightly apart, on a lightly greased baking sheet.
Bake the biscuits in a preheated oven, 180°C (350°F), Gas Mark 4, for about 20 minutes until they have spread slightly. Leave them on the baking sheet for 3 minutes, then transfer to a wire rack to cool. Dust generously with icing sugar.