Trahana is a hard, pebble-like pasta resembling a coarse couscous.It is a traditional pasta eaten throughout Greece and is essentially flour kneaded with sour milk, buttermilk and some salt. The sour trahana is usually added to soups and stews, while it’s sweet version can also be eaten as a porridge. Back in time, it was the only way to preserve milk for the winter, when production was always lower, by mixing it with wheat and drying it, and that’s how the trahana came to life.