In Heston's view, the black forest gateau that most know as that dessert has devolved into something totally inedible, but that it had to have evolved from something really special. He starts his journey of what he considers the classic black forest gateau from its home in Baden-Baden, Germany. Because of its origin, what he sees as the primary ingredient is not the chocolate cake itself but rather kirsch. His creation of the perfect black forest gateau is a six layer concoction of a biscuit base, fruit compote, flour-less sponge cakes, jarred sour cherries, mousses and whipped aerated chocolate, the latter which requires a vacuum cleaner and a space saver storage bag to create. The crowning kirsch glory of the dessert needs to wait until it's served.