I have a meaty frying pan. After quite a number of days of non use I mistakenly used the pan for hot cheese. Can I use the pan again for either milk or meat? Or should the pan be thrown out.?
You can kasher the pan using hagalah, and you don’t have to throw the pan out. Clean the frying pan very well, and make sure there is no residue of oil etc. on the inside and outside of the pan. Then either fill the pan until the top with water and bring the water to a rolling boil. then take a ladle that is also very hot and stick it into the pan, so that the boiling water cascades over the sides of the pan. This will ensure that even the top of the walls of the pan came in contact with the boiling water. Then rinse the pan off with cold water, and it may then be used for meat again.
Although the pan absorbed the milk taste directly through the heat of the fire, and according to some opinions would require libbun, in this instance hagalah would suffice. The reason is that since there was 24 hrs. between when the pan absorbed the meat until the milk was used, therefore he absorbed taste of meat was not a ben yomo, and when the cheese was used on it, it is considered “hetiera bolah”, and therefore hagolah may be done. See Shulchan Aruch Horav O:CH 451-25 and ftnt. to seif 13, Megilas Seferv (m Issur Vheter 93-1, Maadanei Osher ( Issur Vheter) 161-4, Chut Shani (Pesach 10-12(4), Orchos Habayis 10-8, Lehoros Nossan 1-33(1).