The Negi onion is one of the most popular culinary ingredients in Japan, easily distinguished by hollow tubular green tops and elongated stems that never form into actual bulbs. They are mild, savory and sweet, used like green onions, leeks and scallions. Negi onions have a tough texture that allows them to be cooked for long periods and they're also mild enough to eat raw. Negi onions are used to top noodles dishes and hot pot dishes like Shabu Shabu. They're perfect for hearty soups, onion tarts and pot pies and are a great pizza or salad ingredient. You might also try sauteeing them in butter or olive oil and serving as a side dish.