The Whistler Oloroso Sherry Cask is a single malt whiskey with an extra smooth blend of the highest quality malt and grain whiskies. The taste of this whiskey is uniquely fruity with herbs that match The Whistler. This whiskey has matured in bourbon barrels and oloroso Sherry barrels. Nice to know: The name of the distiller Boaan comes from the goddess Boyne of the river and their ingredients come from the Boyne valley.