Heston focuses on the ice cream van, a great British tradition that provided the soundtrack to so many childhoods, and the frozen treats every kid dreams of.
But this wonderful British institution is in danger of extinction. In the 1970s, around 25,000 ice cream vans were on the roads - these days there are less than 5000.
To help kickstart a revival, Heston plans to build the world's biggest ever 99 Flake, over five metres tall and weighing more than a ton, and serve it from the back of his own very special van to the town of Gloucester. He visits Walls and has Europe's biggest ice cream factory at his disposal.
To make his chocolate flake, he ropes in the experts behind the Olympic stadium. Heston also turns the classic flavours of Twister, Cornetto, Feast and Calippo into paint balls that can be fired from specially designed cannons.