Pour a small amount of whiskey into a large bowl. Stir the melted chocolate into the whiskey in the bowl. Gradually whisk in the condensed milk and evaporated milk. Whisk in the cream, coffee mixture and the remaining whiskey.
Pour mixture into 3 x 750ml bottles; seal and store in refrigerator. Best if kept at least 1 month before using.
To serve: shake the bottle well and serve in small glasses over crushed ice.