⅓ cup sugar
2 cups white rum
¾ cup fresh lime juice
6 dashes celery bitters
basil flowers, to serve (optional)
Combine sugar and ⅓ cup water in a jar. Cover. Shake until sugar dissolves. Combine with rum, lime juice and bitters in a large pitcher. Add 8 cups ice.
Stir until ice begins to melt, about 1 minute. Serve over ice, garnished with basil flowers if desired.