A pleasant property of the cast iron skillet is that I can preheat it to an exact temperature in the oven. To make popcorn I drop some ghee in it and put it in and set the preheat to 450. The second the oven comes to temperature I pull it out, put it on medium high add the corn and cover and shake occasionally. Usually have from zero to at most five unpopped kernels this way.

The preheat in the oven trick is good for steaks too.