White onions are a type of onion with a milder, sweeter flavor than yellow onions. They are a good source of vitamin C and fiber, as well as other beneficial plant compounds. White onions can be eaten raw or cooked, and are commonly used in a variety of dishes such as salsas, guacamole, salads, and pickled vegetables. They are easy to find in grocery stores year-round and are typically less expensive than other onion varieties. When selecting a white onion, look for one that is firm, heavy for its size, and has a papery, white skin that is free from mold or soft spots. Store them in a cool, dry place away from sunlight for up to a few weeks. To prepare a white onion, cut off the root and stem ends, slice in half from top to bottom, remove the outer skin, and slice or chop as desired.