Which vegetable is known for its layers?

The onion is famously known for its layers, both in structure and flavor. When cut open, it reveals several thin, concentric layers formed during its growth underground. Each layer is made of swollen leaves that store nutrients and moisture. Onions come in varieties such as red, white, and yellow, each differing slightly in taste and sweetness. They are rich in sulfur compounds, which give them a strong aroma and contribute to health benefits like improved immunity and reduced inflammation. Onions are a staple ingredient in almost every cuisine, used for flavoring soups, curries, salads, and numerous other dishes.