Chill a coupe glass in the freezer or fill with ice while you make the drink.
Add the gin, strawberry syrup, lemon juice, and egg white to a cocktail shaker without ice.
Shake hard for 15 seconds.
Add a generous handful of ice and shake again for 15 seconds until well chilled.
Tip the ice from the coupe glass and strain the cocktail in.
Garnish with a fresh strawberry.
Notes
Strawberry Syrup:To make the strawberry syrup: combine 1½ cups strawberries, 1 cup sugar, 1 cup water and 1 tbsp lemon juice in a saucepan. Simmer for 8-10 minutes, and cool completely. Strain well before use. Full recipe at strawberry simple syrup.