Combine the first 9 ingredient into a cocktail shaker. Shake well for about 25 seconds. Strain the cocktail into a high-ball glass. The piece of melted chocolate is for garnish purposes. -- How to use the melted chocolate: First spread the melted chocolate evenly over a plastic board and leave it to cool and harden.Using a sharp knife, draw the blade across the chocolate to create curls. Add the curls to the top of the cocktail and serve.