Cucumber Mint Syrup:
1 Cup Water
1 Cup Sugar
10 Cucumber Slices
4 Mint Sprigs
Muddle cucumber and mint in a pot, add remaining ingredients. Bring to a low heat (do not boil). Heat on low for 10 minutes then allow to cool for two hours. Strain before using.
Shake all ingredients in an ice-filled shaker (except for tonic), strain into a coupe glass.
Top with tonic and garnish with a salted spiral cucumber ribbon.