Pickled onion

Pickled onions are a food item consisting of onions pickled in a solution of vinegar and salt, often with other preservatives and flavourings. In the United Kingdom they are often eaten alongside fish and chips or as part of a ploughman's lunch. There is a variety of small white pickled onions known as 'silverskin' onions, frequently used as an essential component of the Martini cocktail variant known as a Gibson.