It is the biscuit based quarter-final, and Paul Hollywood and Mary Berry are taking the challenges to another level. The signature bake sees the bakers' organisational and baking skills put to the test, as they attempt to deliver a huge batch of perfectly baked crispbreads. Then the bakers have to throw away the baking rule book as time and temperature work against them to produce six perfectly tempered chocolate tea cakes for the technical challenge. A place in the semi-final will be hard earned as the final challenge tests not only the quality of the bake, but how well it works as a building material. (thetvdb.com)