Despite the fact that humans have been cooking with cast iron for about 2000 years—cooks in the Han Dynasty (206 B.C. – 220 A.D.) used kettles and pans cast of iron—there still exists a ton of mystery around cookware made of the stuff. “Is my cast-iron skillet ruined if it’s rusty?” or “I heard you can’t use soap to clean a cast-iron skillet—is that true?” Don’t worry: We’re here to demystify cooking with cast-iron skillets, and to debunk any myths that surround caring for them.
Thirty minutes isn’t a long time to simmer tomato sauce though – depends on the tomato sauce. Some sauces — all’amatriciana, for instance — should not even be simmered that long. Well seasoned or not, you’ll still get some iron leaching into your food too, but that’s a good thing and the trade off makes it worth it. I choose not to cook acidic foods in my cast iron because I find I have to re-season it more often.