Pickle

You may be looking for gherkin.

A pickle was a processed vegetable that Gwen Cooper ate as she found out that she was pregnant with a Nostrovite egg. She kept some in a jar in her refrigerator. (TV: Something Borrowed)

The Fourth Doctor ate a pickle while at the Gateway. (TV: Warriors' Gate)

Pickle was often combined with cheese in the form of a sandwich. While working late, Toshiko Sato made Owen Harper a cheese and pickle sandwich. (TV: Meat) Graham O’Brien carried a “cheese and pickle sarnie” with him, because he found little time to stop for food when travelling in the TARDIS. (TV: It Takes You Away)

Rhys Williams and Lucy Sobel were served lime pickle as an appetiser at the Indian Summer restaurant. (PROSE: Slow Decay)