A Yellow Onion, also commonly known as brown onion or Spanish onion, is arguably the most ubiquitous and widely used variety of onion globally. It is characterized by its tough, papery, golden-brown or yellowish outer skin. Beneath this skin, the flesh is white, often with faint greenish or yellowish tints, composed of concentric layers.

When raw, yellow onions have a pungent, robust, and slightly sharp flavor that can be quite strong, often causing tearing. However, they transform significantly when cooked, developing a rich, sweet, and caramelized flavor that forms the aromatic base for countless dishes in nearly every cuisine worldwide, from everyday stir-fries in Malaysia to complex stews and sauces. They are excellent for sautéing, roasting, grilling, and braising.