A barm cake is a soft, round, flattish bun from northern England, traditionally leavened with barm.
The original barm cake is found in areas of Lancashire, North West England. Elsewhere in the country, a similar bread roll would be known instead as a "breadbun", "breadcake", "bap, "cob" (a Midlands term referring to a crustier roll), "teacake" (West Yorkshire/some parts of Cumbria; without currants or currant teacake with currants) or even a "stottie," a larger, spongy bread native to North East England.
The Barm Cake is more likely made from commercial yeast today.
Chips are a popular filling, sold in most fish and chip shops in the North West of England often called simply a 'chip barm'. Another popular filling in the North West, particularly Bolton, is the pasty barm. Likewise in Wigan pies are a popular filling, as eaten by TV's Jamie Foster.