Kitchen Expedition

Robert Irvine explores how chocolate went from being a bitter drink with fabled medicinal qualities to the world's favorite sweet. He also sticks his nose into truffles -- the fungus, not the candy -- to find out how they've remained so rare and special.

Robert Irvine investigates two common pantry ingredients. Why was salt once so valuable that it was traded for gold? And how was humble cinnamon originally one of the most-guarded secrets of all time? Robert plans to find out.