¾ oz dry gin¾ oz sweet vermouth¾ oz Gran Classico¾ oz pink grapefruit juice¼ oz lemon juice½ oz simple syrup (1:1)1 egg white1 pinch salt1 top soda water
instructions :

Combine all the ingredients (except club soda) in a shaker and shake until emulsified.
Add ice and shake until chilled.
Strain into a Collins glass over fresh ice.
Top with club soda and garnish.

source :