Into a cocktail shaker, add mint leaves, crush the leaves using a muddler. Add the whole blueberries and muddle as well. 

Add ice, white rum or Blanco tequila, freshly squeezed lime juice, and blueberry simple syrup.

Secure the lid and shake vigorously for 30 seconds.

Strain into serving glass over ice, garnish with fresh mint leaves, blueberry, and a wedge of lime. 

Serve.