Tempered vs Untempered

If you were to watch through a microscope as real chocolate was heated up, you’d see all the fat crystals in the cocoa butter melt. Then, as the chocolate cooled and set again, you’d see the fat reforming into one of six different arrangements. The shape of the fat crystal structure affects the melting point and texture of the chocolate.

Think about the cocoa butter in chocolate like a wall built from Lego bricks. The wall can be broken into individual bricks and rebuilt into different patterns of wall design, some of which are stronger than others.