This is a Mexican-inspired take on the Salty Dog (usually made with grapefruit juice, vodka and salt).
- Wet the rims of 4 glasses and coat with coarse salt (if desired); fill the glasses with ice. Pour 1 ounce tequila and 1/2 ounce liqueur into each. Top each with 3/4 cup grapefruit juice and stir. Garnish with a slice of grapefruit.