Some kind soul posted the recipe for this cocktail on the Guardian website cricket commentary (test series verses South Africa 2012) and I am very grateful for it as it is definitely in my top five cocktails.
The four spirits combine to very good effect and you can not underestimate the contribution of the zest from the lemon garnish. (I like to peel a strip of the lemon peel and wrap it into a tight spiral which can be hooked onto the side of the martini glass.)