This must be the best mojito slushy I've had. You can also make most ahead when party planning. It's a refreshing crowd pleaser.
In a sauce pan over medium heat, cook the water and sugar for about 5 minutes, stirring often, until the sugar has dissolved and the syrup is clear. Set aside to cool to room temperature.
When the syrup has cooled, add it to a blender along with the mint leaves, lime juice and zest and Bacardi Rum. Blend to combine.
Add ice and pulverize into a slushy. Float extra rum on top and garnish with mint and limes.
Tip: If making ahead of time, blend all ingredients except the ice. Store in a covered container in the refrigerator until you're ready to blend with the ice and serve.