And really, why is it called a greyhound? Grapefruit juice is tangy and bright. It should be called a Chihuahua or something. Anyway.
I made one with mint the other night. It were tastee.
Squish yourself some grapefruit juice.
Throw a few leaves of fresh mint into the bottom of a glass. I grow my own mint, and the leaves are itty-bitty right now.
Mush the heck out of the mint to release the oils in the leaves. Add a shot or two (I won't judge) of vodka.
Add the juice, through a sieve preferably. Stir gently...
And there you go. A greyhound. If you want an ice-cold greyhound sans mint leaves, mix the drink in a shaker with ice, and strain the mint out. If you're a pantywaist and grapefruit juice is too sour for you, add a teaspoon of superfine sugar.