Black peas, also called parched peas or maple peas, form a traditional Lancashire / Greater Manchester dish served often, with lashings of malt vinegar, on or around Bonfire Night (5 November). The dish, popular in Bury, Preston, Rochdale, Oldham, Wigan, Bolton and Heywood is made from the purple podded pea (Pisum sativum var. arvense) which is soaked overnight and simmered to produce a type of mushy pea. Parching is a now defunct term for long slow boiling.