I do most of my cooking in cast iron skillets. I have two Griswolds and a Wagner both given to me by my grandmother. As I use them more and more, I have been wondering about how best to take care of them. Here are the basics of what I do:

- Wash very shortly after cooking using hot water and a sponge. No soap of any kind.
- Dry immediately
- Lightly coat cooking surface with vegetable oil

Here is what I have some questions about:
- One resource, I came across, recommended heating the pan over low heat before applying the coat of oil. However, they gave no reason why you should do this. Does anyone else do this? Why would they recommend doing this? My initial thought is that the warm skillet will better absorb the oil, but I don't know.

- A cast iron cookbook I have recommends storing your skillets in the oven, but not removing them when you use the oven. The idea being that each time you turn the oven on the pan reseasons itself. What do ya'll think? I tried this for the last week or so with mixed results. If I was heating the oven to less than 400 degrees, I left my skillets in there turned upside down. After doing this 6-8 times, the skillets are maintaining their nonstick surface and in some cases performing better. But, they now have what appear to be "oil spots." The cook surface is covered in these slightly-raised, shiny-black spots. These spots have not had any affect on my cooking. I can fry eggs and cook pancakes without a problem in each of my skillets. But, I still wonder about doing this for the long term. What do you think?

Any other thoughts and comments on cast iron care will be greatly appreciated.
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