Last Sunday night on the premiere episode of Chopped All-Stars, the Iron Chef contestants opened up their baskets to find sour trahana. I quickly found myself Googling the term, only to find out several minutes later from Ted Allen that it's a traditional Greek pasta that is essentially flour kneaded with sour milk, buttermilk or yogurt and some salt.

I couldn't get a good glimpse of the grain on TV, but imagine a substance similar to couscous.

According to The Food and Wine of Greece by Diane Kochilas, "Until a generation ago, sour trahana was the shepherd’s and farmer’s breakfast. It was made at the end of every summer all over Greece in preparation for the winter months."

So what can you do with sour trahana? Try cooking it in a soup, like Cat Cora's Chicken Soup. The longer you cook the grain, the thicker it becomes.

If you can't find sour trahana in the international aisle of your local supermarket, try searching for it online at a Greek specialty store.

Tune in this Sunday at 9pm/8c when four gourmet globetrotters — Keegan Gerhard, Marcela Valladolid, Jeffrey Saad and Aarti Sequeira — take their place on the Chopping Block.