London particular is a traditional soup made from dried whole peas or yellow or green split peas. They're combined with ham, ham hock, bacon, or gammon, while vegetables such as carrots, celery, and onion are added for extra flavor. The traditional London version uses yellow split peas exclusively.

When properly prepared, the soup should be so thick that a spoon can stand upright in it. London particular is typically served as an appetizer or main dish with crusty bread on the side. The name of the dish comes from the thick smog with a yelowish tinge by gas street lamps, which looks similar in texture and color to pea soup.

The term London particular was further popularized by Charles Dickens in his novel Bleak House. In the 19th century, the soup was a street food staple in stalls and taverns of London, but nowadays very few restaurants serve it occasionally.