0.5 oz. Orange Liqueur (Cointreau, Combier Liqueur d'Orange, Aperol or any Triple Sec will work)
0.5 oz. Agave Syrup (simple syrup or honey can be substituted in a pinch)
3 oz. Double Dutch cucumber margarita mixer
Add Highclere Castle Gin, orange liqueur and syrup to a shaker with ice. Shake and strain into a glass with ice. Top with Double Dutch mixer. Garnish with a cucumber ribbon.