Yesterday, I got a cast-iron skillet, and the first thing I did was try to season it. I washed it vigorously with soap and water, then rinsed it for several minutes.
After drying it with a paper towel, I put it on the stove and started up flame on the medium setting. Then I took a brush, which I used to cover the entire (hot) cookware surface with oil. By this time, my oven had been preheated to 350 degrees Fahrenheit, and I put the skillet in for 30 minutes.
After taking it out and letting it cool, I found that the patina looked terribly sticky, and I could still see and feel the coarse original cast-iron finish. A bit of research revealed that this is because (i) because I used too much oil and (ii) because olive oil isn't good for seasoning. Oh well. I washed it out (soap and water), dried it, and placed it on medium heat for 10 minutes so that it wouldn't rust. I turned the heat off after 10 minutes, and went to bed to try it again with canola oil today.
To my shock, I found the following on my skillet (two pictures of the same skillet). Look at the edges of the dark spots to see what I mean:
Is this rust? Or is it some strange transition material between the seasoning patina and the cast-iron? How did this get there, and what can I do about this (in the present to fix and in the future to prevent)?
Additional questions (I'm a beginner, so I have a few):
- Do I need to remove what looks like a partial olive oil seasoning layer from the skillet?
- What oil should I use for the new seasoning? At what temperature should I heat it?
- Should my skillet be room temperature when I apply the oil?
- Should my skillet be in the oven when the oven is preheating?
- Does heating the skillet after washing and applying a bit of oil to it before storage promote rancidity?