The Welsh onion (Allium fistulosum) is the true bunching onion — a hardy perennial allium that never swells into a single round bulb but grows as a clump of thick, upright, hollow-leaved shanks, cut and divided again and again through the year. It is the cornerstone allium of East Asian cooking: the long, fat, white-blanched naga-negi of Japan and the everyday cong of China, where the pale lower shaft is meltingly sweet when cooked and the hollow green tops are fresher and grassier raw. Thicker, tougher and far more perennial than a Western scallion, it is grilled whole in yakitori, layered into hot pots and sukiyaki, simmered into stocks, and shredded raw as the shiraga-negi garnish over ramen and grilled meats — an aromatic backbone rather than a mere finishing scatter.