Prep Glass: Fill a Martini or Coupe glass with ice. Give it a quick stir and set it aside.
Add Saline Solution: Pour a few drops of saline solution into the cocktail shaker; start with only 2 or 3 as saline solution is usually very concentrated.
Add Grapefruit Juice: Pour 1 oz fresh grapefruit juice into the shaker.
Add Triple Sec: Add ½ oz Triple Sec.
Add Campari: Follow this with ½ oz Campari.
Add Mezcal: Finally, add 1½ oz Espadín Mezcal to the mix.
Shake Well: Fill the shaker with ice, close it and give it a good shake (10-15 seconds). Give it a taste and add a few more drops of saline solution if necessary.
Strain: Take the Coupe or Martini glass and discard the ice inside. Then, using both the cocktail strainer and the fine strainer, strain the shaken drink into the chilled glass.
Garnish: Garnish with a grapefruit zest twist: to do so, express the lemon zest on top of the glass (you can either discard it after or place it on the rim of the glass for an added citrus touch). Serve immediately.