I wish I would have looked up to see that the burner was still hot, although I should have known I had just moved the pan off the hot burner. I wasn't quite sure how to tackle the problem. After doing a little research, I settled in on a mode of attack. Let me just say, there are plenty of other ways to do it...some while the burner is still hot. But I needed to focus on getting dinner finished so we could eat before 9pm. First let the burner completely cool.
Get some ice cubes and put them right on the melted plastic. Let this sit for a couple of minutes. This will cause the melted plastic to shrink up a bit so you can "pop" it off with a straight edge.
Gently use your straight edge (one sided razor blade, or thin metal spatula) to lift off the plastic.