The scallion (Allium fistulosum), known equally as the spring onion, green onion or salad onion, is the youthful, slender allium of the kitchen — a small white base topped by long, hollow, blue-green leaves, harvested before it ever swells into a fat bulb. Both ends are eaten: the firm white shank carries a gentle onion bite while the green tops are fresher, grassier and milder, with a clean sweetness and far less of the harsh sting of a mature onion. Sliced raw it is the bright finishing scatter on noodle soups, tacos, dumplings and salads; laid in a pan or over coals it softens, sweetens and chars; and folded into batter it becomes the savoury heart of a Chinese scallion pancake or a Korean pajeon. It is one of the most universal aromatics on Earth, anchoring East Asian cooking yet at home in almost every cuisine.