Tear mint leaves into small bits into mortar (the kind that goes with a pestle).
Add sugar into mortar.
Add splash of tonic water into mortar.
Mull this mix with pestle until you can smell mint.
Add juice of 1 lime.
In small beverage glass add ice and rum.
Add mixture to beverage glass.
Top with Tonic Water.
Stir, serve, and enjoy!