RFC Certified Unofficial Website food

Seasoning cast iron (thank you to Tom Rankin)

Summary:

Make sure your cast iron is clean down to bare metal.
Coat with fat, heat, repeat.
Look after by never washing in soapy water and scrubbing as little as possible.

Details:

Initial cleaning: get off all the packaging oil, burnt food or whatever the pan has on it. Some suggestions for achieving this are

- Wash in hot soapy water, dry thoroughly
- Boil undiluted white vinegar in the pan for while
- Commercial beadblasting (not sandblasting)
- Steel wool
- Hot embers
- Kosher salt baked in the pan at 500°F (260°C) for 4 hours and scraped out again
- Put in self-cleaning oven and turn on clean cycle,

Fats to use: a solid vegetable fat, or lard. Oil is not as suitable.

Seasoning process:

Wipe pot inside and out with melted fat. Do the lid too (if it's cast iron). At this point, authorities seem to diverge. The common theme is "get it hot and keep it hot for considerably more than an hour" (optionally followed by "re-coat it with fat during the process"). Two hours at 350°F (175°C), re-wiping with fat every 30 minutes, seems sensible.

When this has been done, the seasoning process has been begun but not yet completed. The first few times the pan is used, it should be for fairly fatty foods. Fried eggs rather than tomato soup, for example.

Each time the pan is used, rinse with hot water and scrub if necessary. Don't scour or use detergent - otherwise you will need to re-season. Some people coat their cast iron very lightly with oil after washing, then wipe out after an initial heating next time they use it.

NB: this is an extract from the RFC FAQs.