Pour rum, lime, and sugar syrup into a lowball glass – add crushed ice and 6-10 mint leaves.

Churn – so the bottom of the cocktail is mixed with the rest of the glass via a bar spoon.

Fill the rest of the glass with crushed ice and top with soda water (If there is no crushed ice, use a shaker to mix the cocktail. Use a fine strainer to remove mint bits from the cocktail. Remember to top with soda water afterward, not before – otherwise, the carbonation creates pressure in the shaker).

Garnish with mint sprigs & lime.