To make chocolates, or bonbons, chocolatiers start by choosing their couverture, or inventing their own blends. For chocolatiers, the art of covering or enrobing bonbons in a perfectly glossy, smooth coating of couverture is a major source of pride and prestige. Instead of simply melting their chocolate, which can leave it dull-looking, chocolatiers use a process called tempering. Repeatedly heating and cooling the chocolate changes its molecular structure, which makes it shiny and gives it the snap that is a hallmark of good chocolate.