Matt Lucas hosts as TV presenter Stacey Dooley, Little Mix's Jade Thirlwall, comedian Katherine Ryan and internet influencer KSI show off their baking skills. They serve up cocktail-flavoured fondant fancies, have their knowledge of pastry tested in the technical and in the showstopper are asked to create a scene showing something they cannot live without - all from biscuit and meringue. Paul Hollywood and Prue Leith judge their efforts