Combine 60ml gin, 30ml fresh lemon juice, and 15ml simple syrup in a cocktail shaker.
Fill the shaker halfway with ice cubes.
Shake vigorously for 10–12 seconds until well chilled.
Double-strain into a chilled whiskey sour glass over fresh ice.
Garnish with an orange slice and a maraschino cherry on a cocktail pick.
For a silkier, more classic presentation, add one egg white before shaking - dry shake first without ice to build the foam, then shake again with ice for the best texture and a beautiful frothy cap.
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