Barmbrack

Barmbrack , also often shortened to brack, is a yeast bread with added sultanas and raisins. The bread is associated with Halloween in Ireland, where an item (often a ring) is placed inside the bread, with the person receiving it considered to be fortunate. It is sometimes called bairín breac, and the term is also used as two words in its more common version. This may be from the Irish word bairín - transl. a loaf - and breac - transl. speckled (due to the raisins in it), hence it literally means a speckled loaf (a similar etymology to the Welsh bara brith). Other origins for "barm" could relate to the use of the froth from fermented ale, which is a form of yeast referred to as barm. This was used in place of bicarbonate soda in baking, as it was not widely available in Ireland until the early 19th century.

Source: Wikipedia