In week six there's a savoury signature, where contestants must impress judges Paul Hollywood and Prue Leith with style and substance. There's also a multi-layered technical, and an ambitious final challenge, in which the bakers make a traditional pie. Sandi Toksvig and Noel Fielding are with the contestants every step of the way, ready with a pertinent pep talk or just a sympathetic shoulder to cry on. Also, Sandi heads abroad to discover how some unusual habits have inspired a classic pastry treat.