Muddle all but the spirits in a shaker. Add spirits, shake with ice, and strain into a chilled rocks glass filled with large ice. Garnish with a pineapple leaf.
A smooth Scotch like Aberlour will also work in place of Irish whiskey. Because of the prominence in the drink, smoothness is important; you don't want anything with too much of a bite, like Speyburn speyside scotch.