Fill a coupe or martini glass with ice cubes and set aside.

In a cocktail shaker, muddle the 5-7 mint leaves with the lemon juice.

Add ice to the cocktail shaker with the muddled mint and lemon juice. 

Add the gin and simple syrup to the cocktail shaker. Shake until very cold, about 30 seconds.

Remove the ice from the coupe glass and strain the cocktail into the glass.

Garnish with 1-2 mint leaves.