This is the original westside v southside story. Al Capone's gang smuggled in a gin that was super harsh and unpalatable. After forcing a bartender at knife point (probably) to make something they could drink with it - someone came up with a drink that was made with citrus, sugar and mint. The drink became known as the Southside and as legend goes, was Al Capone's drink of choice.
50ml x Poor Toms Sydney Dry Gin
30ml x Lime juice
15ml x Sugar syrup
6 x mint leaves
1. Add all ingredients to the shaker
2. Add plenty of ice and shake hard
3. Strain into a chilled martini glass and garnish with a mint leaf.