As an ode to the salty rim of the serving glass in which the drink is poured, the gin variation is a spin on the classic one which uses vodka. Minimal and simple but big on flavour, experiment with an assortment of gourmet salts for added depth and complexity.
Moisten the rim of a highball glass and dip it in coarse salt.
Fill it with ice before adding the gin and grapefruit juice to stir gently and combine.
Garnish with a grapefruit slice before serving.