Fill a highball glass with ice cubes. Add all ingredients. Garnish with orange.
The orange is less frequently used in the bar than its more acidic cousins, the lemon and the lime. But it makes a very good garnish - not the least as here, in wedges, or as an orange twist. Use a zester or a knife to cut a loooong spiral of orange peel. Put it in the glass, add ice, and then build the drink as usual. Very stylish.