Thank you, Rabbi Sperling, for your quick response. Id like to understand the source for your response. I had learned that nonstick coatings could not be kashered, so Im happy to learn something new.

Shalom, Thanks for getting back to us. You are correct in thinking that there is an issue koshering Teflon pans. Most Rabbis do not permit it, due to the fact that it would need to get very hot, and might be ruined – they therefor forbid such koshering due to a worry that people will not get the pan hot enough. However, Rav Moshe Feinstein zt”l (Igrot Moshe, Even HaEzer 4, at the end of responsa 7) rules that Teflon may be koshered. However, beyond that basic question, your case raised a different issue. That is, it was never unkosher. It had absorbed kosher milk taste, but never any forbidden taste. In halacha this is called “heter ba’lah” – it absorbed permitted taste. In truth there are opinions that allow you to cook parve food in it even with the intent of eating them with meat, without any koshering of the pan. This is because the milk taste would only be absorbed into the parve food as a secondary taste, and that level of taste may be mixed with meat (“Nat bar Nat”). There are many details about such laws (differing between Ashkanazim and Sephardim, spicey foods or not, if the pan had not been used for 24 hours etc). Because of this, it would be advisable to kosher the pan, especially if you plan to use it for parve food that will be eaten together with meat (and all the more so if the parve food is very spicey). None the less, even if you did not kosher the pan at all, and went ahead and cooked parve food in it, and that food was mixed with meat, it would still be 100% kosher both for Sephardim and Ashkanazim! But, ideally it would be correct to kosher the pan before doing such cooking. With all that in mind, we now need to examine how to kosher a pan that only absorbed permitted taste. This level of koshering requires what we call “libon kal” or “light heating”. That is, it does not need to reach red hot, sparks flying, hot – (which, you will recall, is an issue with Teflon pans – see above), but only hot enough to singe a piece of straw. This level of heat can be done on all pans, as there is no fear that it will ruin the pan. I hope this is of some help, Blessings.