How a factory in Essex produces 400,000 cereal bars a day - from nuts to cranberries and sultanas to puffed rice, with a carefully balanced blend of honey and glucose binding it all together for the ideal texture. How macadamia nuts are harvested in South Africa, and shelled under extraordinary pressure. The scientific distinction between botanical nuts, legumes and drupes. The history of Britain's cereal bars, including one Kendal Mint Cake snack bar made popular by famous explorers Ernest Shackleton and Sir Edmund Hillary.