Place the mint leaves in the bottom of a medium size pot with a heavy bottom. Use a muddler or a wooden spoon to crush the mint. Add the sugar and 1 cup of water to the pot, then bring to a simmer over medium-high heat, stirring to dissolve the sugar. Once the sugar is fully dissolved remove from heat and allow the mixture to steep in the pot until cooled to room temperature. Strain the cooled syrup through a fine mesh sieve, pressing on the solids with a spoon to extract as much of the l...