Reconditioning and Re-Seasoning Cast-Iron Cookware is not as difficult as it may seem when first broaching the topic. While words like ‘reconditioning’ and ‘re-seasoning’ may come across as intricate processes that require experience in the culinary field…that is not the case. On the contrary, both acts can be completed with just a few household items and a small amount of spare time.
Start by spraying any of your best cookware with an oven cleaner (any brand is fine), and enclosing the cookware within a sealed plastic bag for between 2-5 days. The length of the plastic bag phase truly depends on personal preference and condition of the cookware before bagging.
Once the bag has sat for an ample amount of time, remove it and softly scrub it with water and basic dish soap. This will wash away excess buildup of oven cleaner and what it extracted from the pan over those few days within the bag. Using an industrial brillo pad, remove all excess rust that is visible and able to be removed. For any excess buildup, use a combination of white vinegar and water—leaving it to sit for 30 minutes at a time. Now that excess grease, residue, old food, and bad memories have been removed from your cast-iron cookware, it is time to season it now.
Next, take care to lay down some combination of aluminum foil, baking sheets, or makeshift liquid catchers at the very bottom of your oven to ensure that drippings do not cause to smoke buildup within the oven during the re-seasoning process.
Preheat your oven to 150 degrees and allow it to sit (free of cookware) for 10-20 minutes to ensure that excess moisture evaporates within the oven before you place any pieces of cookware within. Once you are certain that the oven is ready to be used—place your cast-iron cookware in the oven until they have been heated to the 150-degree temperature. It is at this point (perhaps 12 minutes later), that you remove your pan(s) and apply Crisco shortening evenly within the pan.
Return your cast-iron cookware to the oven, raise the temperature to 250 degrees, and leave any seasoning cookware within the oven for 30 minutes. At the end of the 30 half-hour, remove your kitchenware and wipe it down to a shine—this should represent the first good session of conditioning and seasoning for your precious cast-iron cookware pieces.
If you’d like to season your cast-iron pieces more thoroughly, feel free to repeat the Crisco and oven-related options as often as necessary until you are satisfied with the result. The goal is to not destroy the surface of the cast-iron while restoring necessary levels of seasoning. Do not become overzealous with any step along the way—soaking, oven cleaning, shutting up in a Ziploc bag, vinegar use, and oven heat—that will only lead to irreparable damage to your cast-iron pots, pans, and skillets.