Cast Iron

For cleaning, I used a spray can of Easy Off oven cleaner, specifically one with a yellow cap and specifically says that it contains lye (aka sodium hydroxide). I preheated the pan to 200 F (~90 C) in the oven for 20 minutes, and the withdrew it and immediately sprayed it with Easy Off. The pan then went into a plastic garbage bag, the bag set inside of a 5 gallon bucket for support, and the bag wrapped shut. This will keep the vapors circulating within the bag, exposing more deposits to its chemical effects.

After a day, I removed the pan from the bag and washed it down with generous water, to dilute the sodium hydroxide. The pan was then scrubbed down with a nylon brush to physically remove crusty material. To dry off the water, I put the pan into the oven again at 200 F for 20 minutes. The bag should also be washed with generous water before reusing it for standard trash service. Wear gloves.

Once I got the pan suitably stripped, I followed my original process, described here: https://sh.itjust.works/comment/15774888

Essentially you scrub it down with steel wool to remove any rust.

Then, you rub it down with a really thin coat of oil, preferably flax seed oil.

Then you stick it in the oven at 500F for an hour, then turn off the oven with the pan still inside. Let it all cool down over time.

Then repeat the oiling and heating process a couple more times.

In addition to what the others have said. For stripping a really bad pan you can leave it in the oven during the oven’s self-cleaning cycle.