Scallions, also known as bunching onions, are a mild, [tender allium sometimes sold as “green onions”](https://www.masterclass.com/articles/scallions-vs-green-onions-whats-the-difference) at the grocery store or farmers market. \n\nThey most likely came into popularity as regular young onions picked early in the growing season, before their bulbs fully developed and their green leaves dried out. Today, farmers grow multiple varieties of onion specifically bred to be harvested at this stage, such as Evergreen Hardy White and White Spear. While part of the same species as the common bulb onion, these scallion varieties, also called “bunching” due to the fact that they grow in small clusters, can be grown year-round, and never form a true bulb. It’s these varieties that you’ll find at supermarkets, labeled as both scallions and green onions.\n\nLike other alliums, scallions contain sulfuric compounds that protect them from predators. This is what makes you cry when chopping onions, and what gives raw onion its bite. (Tip: Toss onions in the fridge before slicing to avoid tears.) Onions take up sulfur from the soil to produce this defensive oil, which releases when they’re bitten or cut. When cooked, these chemicals transform from harsh to savory. The volatile oils escape whenever onions are damaged, so make sure to rinse scallions before cooking—when exposed to air, the scallions’ defense mechanism can taste extra harsh. \n\nScallions should be sliced—not chopped—using the entire length of the blade of a sharp knife. To slice scallions:\n\n- Clean scallions, stripping away any damaged or rotten outer leaves from the green stems, and lay a few in a single layer\n- Place the tip of the blade against the cutting surface\n- Pull backwards steadily across the scallions\n\nDo not chop scallions: Downward pressure can bruise their delicate leaves. [Watch Chef Gordon Ramsay](https://www.masterclass.com/classes/gordon-ramsay-teaches-cooking-restaurant-recipes-at-home) demonstrate how to slice scallions.\nWhen grocery shopping, choose scallions that have: \n\n- Firm, undamaged stalks \n- Bright green leaves \n- Moderately dry flesh (or, those that are not dried-out or slimy). \n\nTo keep scallions fresh, store them in the fridge, in a jar with about an inch of water. Place a plastic bag over the greens and secure with a rubber band to keep them from wilting, and change the water every day or two. \n\nScallions refrigerated in water can last a week or longer. You can also freeze sliced scallions to extend their shelf life, but their texture will change when defrosted, so previously frozen scallions should only be used in cooked preparations, not raw. \n\nThe entire scallion plant is edible, from its green stalks down to its white roots. Scallions are mild enough that both the whites and the greens can be eaten raw, as in scallion salad, a popular side dish for Korean barbecue, or as a crunchy garnish for soups, chili, [and potato purée](https://www.masterclass.com/articles/gordon-ramsays-recipe-for-pomme-potato-puree). Raw scallion whites and greens can be pickled whole or fermented in kimchi. \n\nWhole scallions are delicious grilled or roasted—the leaves become charred, the whites tender and sweet, and the toasted roots have a nice crunch, like an onion chip. (While edible, raw scallion roots are typically too tough to enjoy.)\n\nMany stir-fry recipes call for separating the whites and the greens. This method mellows out the sharp flavor of the white bulbs, while allowing the raw greens to stay fresh as a garnish. An added bonus? The scallion whites are usually the first ingredient in the wok, infusing the cooking oil with their aromatics and flavoring the rest of the stir-fry.\n\nAs part of the genus Allium, scallions share their characteristic onion flavor with several edible species and hundreds of onion varieties. But because scallions have a milder flavor than most onions, direct substitutions can be tricky. A good rule of thumb, however, is to substitute bulbs for bulbs and leaves for leaves. \n\nSubstitutes for scallion whites include: \n\n- __A small amount of bulb onion__. Raw onions will have significantly more bite than scallions, so make sure to use less.\n- __The white part of a leek__. In cooked preparations, heat will soften the sting of a more traditional onion, but the sweetness will also become more pronounced. Leeks are a good substitute for cooked scallions as they are closer than a yellow onion to the desired clean, savory flavor.\n- __Half the stated amount of spring onion__. Spring onions have a stronger flavor than scallions and should be used in smaller amounts than what the recipe calls for. \n\nFor the best substitutes for scallion greens, try: \n\n- __Fresh chives__. When used as a garnish, fresh chives are a great substitution for scallion greens. Because chives have a milder flavor than scallions, you’ll need to use more of them, and they won’t have the same kick. \n- __Spring onions__. The tops of spring onions—if they aren’t too tough—provide the closest approximation to scallion greens.\n\nDo not substitute the green tops of leeks for scallions—they’re too tough to use raw, and become slippery when cooked. \n\nScallions are an excellent source of essential nutrients.\n\n- __Vitamin B2 (riboflavin)__, which is essential to energy production and metabolism.\n- __Vitamin K__, which plays a role in blood clotting and bone and muscle health.\n- __Vitamin C__, which is an antioxidant that supports the immune system.\n- __Calcium__, which maintains the structure of bones and teeth.\n- __Iron__, a component of hemoglobin, which transfers oxygen from the lungs to the rest of the body.\n- __Potassium__, which supports kidney, heart, muscle, and nerve health.\n- __Dietary fiber__, which helps you digest food.\n\nThe green tops of scallions are a very good source of:\n\n- __Vitamin A__, which supports the immune system and vision.\n- __Vitamin B6__, which plays a role in metabolism and the immune system.\n- __Vitamin B1__ (thiamin), which is integral to cell growth and function.\n- __Phytonutrients__ (antioxidants), a broad class of plant-based compounds which promotes overall health.\nScallions contain less carbohydrates and protein than other onions; moderate amounts of scallions—especially the greens—are a good option for adding flavor and nutrients to most healthy diets, including keto. \n\n\nBecome a better chef with the [MasterClass Annual Membership](https://www.masterclass.com/). Gain access to exclusive video lessons taught by culinary masters, including Gordon Ramsay, Chef Thomas Keller, Massimo Bottura, Dominique Ansel, Alice Waters, and more.\nHouse rule: at least one bunch of scallions in the crisper at all times.