Tip the chopped mango into a blender and blitz with 50ml water (you may need to add a little more if it's a large mango).

Pour the blitzed mango juice into a cocktail shaker with the mezcal, lime juice and agave syrup. Fill with ice and shake until the outside of the shaker feels ice cold. Strain the cocktail into a martini or coupette glass and garnish with a mango peel twist.