Pontefract cake

Pontefract cakes are a type of small, roughly circular black sweet measuring approximately .75 in (19 mm) wide and 0.16 in (4 mm) thick, made of liquorice, originally manufactured in the Yorkshire town of Pontefract, England. The original name for these small tablets of liquorice is a "Pomfret" cake, after the old Norman name for Pontefract. However, that name has fallen into disuse and they are now almost invariably labelled "Pontefract cakes". The term "cake" has a long history. The word itself is of Germanic origin, from the Germanic "kakâ" (cook).

Source: Wikipedia