This is a variation on the classic cucumber relish that is omnipresent in the cuisines of Southeast Asia. Various versions of this simple, spicy relish appear in restaurants, street stalls, and homes throughout the region, but none contains watermelon - or at least none that I've seen. But I think it works, and it is truly international because guess what the Number One most popular fruit of the world is? That's right, watermelon. This is a good relish with grilled shellfish of any variety.
