As good as traditional cast iron is for those one-pan meals and steaks, there are certain foods that you should avoid cooking in them.
First are those that tend to leave strong smells behind such as garlic, peppers, and some types of fish. The lingering odor that will stay in the cast iron may ruin the other dishes that you will cook after.
If your cast iron pan is new, avoid frying eggs with it also. However, once the pan is already well-seasoned, there won’t be a problem anymore.
Fleshy fishes can be able to stand the heat of cast iron pans but not the delicate types such as trout and tilapia. You can relegate them to a non-stick pan.
Acidic food is said to have a reaction to metal and thus should not be cooked in cast iron as well. Others believe that acid will discolor and break down the seasoning of the pan.