Chocolate biscuit

A chocolate biscuit is a biscuit which is covered in chocolate, or which has been made by replacing some of the flour with cocoa powder. Chocolate biscuits are quite popular in places all over the world, particularly the United Kingdom. The composition and recipe may vary considerably and there is often legislation to specify how the biscuit may be described. In the United Kingdom, a biscuit made without an external coating may only be described as "chocolate" if it contains at least 3% of dry cocoa solids. If there is a coating, this must contain cocoa butter as the fat to be described as chocolate, rather than just "chocolate-flavoured". In 1891, the Cadbury brothers filed a patent for a chocolate-coated biscuit.

Source: Wikipedia