A fruity, refreshing, summer cocktail.
For mint simple syrup: Combine water, sugar and mint in microwave safe container. Cook until sugar is dissolved. Let it stand for a few minutes and strain.
For cocktail: Combine 1/2 ounce of the mint simple syrup, watermelon juice, rum, and vodka in an ice filled glass. Top with sparkling water. Garnish with a sprig of mint.