Place the dried fruits in a large bowl, pour over the brandy and whisky syrup and stir well.
Cover with clingfilm and leave to soak overnight.
Add the remaining pudding ingredients and stir well.
Grease a 1.2 litre (2 pint) pudding basin with butter. Fill it three-quarters full with pudding mix. If you are using a lidded basin, secure the lid. If you are using a traditional ceramic pudding basin, cover with a double layer of buttered, nonstick baking paper that’s pleated in the middle, followed by a layer of foil. Tie the string tightly around the rim and make a loop of string to use as a handle.
Put an upturned, heatproof saucer in the base of a large pan and sit the pudding basin on top.
Pour boiling water into the pan so it comes halfway up the side of the basin. Cover the pan and bring to the boil. Reduce the heat and simmer for 5 hours, topping up with boiling water when necessary, until a skewer comes out clean.
Invert the pudding onto a serving plate, dust with icing sugar and top with holly. Serve with whisky butterscotch.