1879 CE
Rodolphe Lindt invents the conching machine, which creates chocolate that melts in the mouth

In 1879, Rodolphe Lindt invents a machine that heats and rolls liquid chocolate mass to refine it. After the chocolate is 'conched' more cocoa butter is added, creating a texture that 'melts in your mouth'.

The magic of the conching process was actually discovered accidentally, when Rodolphe Lindt left his factory on a Friday without turning off the chocolate machines. The following Monday, he came back to the factory and discovered that the extended period of mixing had dramatically affected the chocolate. He experimented further and ultimately developed a special grinding machine (which looked like a conch shell, giving it its name).

Source: The invention of LINDT chocolate (2015). Lindt.com.