Fill a milkshake sundae glass to the top with ice cubes
Place the pulp of a watermelon wedge into a shaker and muddle
Pour in 0.5 oz of lemon juice and 0.75 oz of passionfruit syrup
Fill the shaker with ice cubes and shake
Finely strain into the milkshake sundae glass
Top up with ginger beer and stir gently
Garnish with a piece of watermelon on a cocktail skewer