Cast iron is tough stuff. It's heavy, hearty and happy to take the heat.
But once cast iron has seared the steak, sweated the onion or swirled the sauce, it casts off the role of stove-top hero. After hours, it's all diva. The buff and blackened skillet takes one look at the dishwasher and goes faint with fear. Even the sudsy basin gives it the vapors. No soap — too harsh for that gleaming complexion. No water — might rust that burly build. No scrubbing — could scratch that fine patina.
Leaving the pan handler few options. A brief buff with a dish towel, perhaps. A strong glare. Or this technique, found in a French fairy tale: Use a stale chunk of bread as a sponge, oil instead of water and salt as scrubbing agent. Works like a charm. And why not? Tough sorts can use a little tender.