Make Lemon Sugar
Prepare your martini glass with a rim of lemon sugar (rub lemon zest into a plate of sugar until tinted yellow and fragrant). Dip moistened martini glass rim in sugar and set aside.
Add Lemon Drop, vodka, Cointreau, and a handful of ice to a cocktail shaker. Shake for 30 seconds or until very cold. Strain into the prepared martini glass and serve immediately.