I use Dritz "Iron Off". I've used it on both Teflon bottomed irons and those with shiny sole plates. Works great on both. Tube lasts quite a while. Use it on hot iron - put Iron Off on an old wash cloth or thick fabric. Rub iron over the Iron Off and goo/stain lifts right off. Make sure you clean the steam vents (run steam through the iron to clear out any Iron Off that may have gotten into the vents). Using a wet cloth, run the iron over it to clean off the sole plate. Iron away with a spotless iron!
Anita