Add coconut rum, fresh lime juice, and simple syrup to the shaker.
Shake vigorously for 10-15 seconds until well-chilled.
Double strain the mixture through both strainers into a chilled martini glass or coupe.
Garnish with a lime wheel on the rim of the glass.
Notes
Fresh lime juice makes a big difference in taste compared to bottled juice. One medium lime yields about 1 oz of juice.Store coconut rum at room temperature. It stays fresh for up to 6 months after opening.Make simple syrup by combining equal parts sugar and water in a pot. Heat until sugar dissolves, then cool before using.Pre-chill glasses in the freezer for 10 minutes before making drinks.