Fill a cocktail shaker with ice. Add all of the remaining ingredients except the garnishes and shake well. <a href="/articles/cocktail-basics-techniques#doublestraining">Double strain</a> into a chilled martini glass. Pinch the orange twist over the drink, rub it around the <a href="/articles/cocktail-basics-techniques#rimmingaglass">rim</a> of the glass, then drop it into the drink. Garnish with the remaining mint leaf.