I guess heating the jar could slow the cooling time but, honestly, pouring at 160 the jars got so hot I can't comfortably touch them. Slower cooling does seem to help frosting as I see it appear at the bottom sooner than the sides. That said, everything can look great and then the following week, wham, there it is and it progresses all around the container given enough time. For now I'll take the better tops that I get at 160 pours and see if the frosting goes away when the humidity drops and also consider no dye. As one poster said in the archives about frosting, once you start burning the candle the frosting appears too.