Suppose that I have a cast-iron pot which my awful roommate has vigorously scrubbed with soap and left to soak in soapy water over the weekend. The seasoning has been destroyed and replaced with awful-tasting soapy contaminants.
It seems to me that the simplest and best way to deal with this is to heat the pot over a campfire until only black carbon remains, then clean and reseason.
Not knowing exactly what is in my awful roommate's dish soap, and being a very fussy foodie, I want to be conservative here... so how hot would I have to heat the pot, and for how long, to be quite sure that virtually nothing but carbon remains?
Edit: Compare using the self-cleaning cycle of an oven for similar purpose, reported to work well...