For me, it's easy. CI is durable, easy to clean, and I can cook just about anything in it, from cakes, to fried chicken, to stews, even spaghetti sauce and chile. My CI has seen years of use and has been taken camping and cleaned in a stream while scouring with sand. And it's still around and working great. Try that with your clad SS or teflon non-stick pans.
I can't think of any food, off the top of my head, that I haven't made in cast iron at one time or another. For instance; you want extraordinary pizza? Put some olive oil into a 12" cast iron pan and place your pizza dough in that. Put on the toppings. Place the pan onto a Webber Kettle charcoal grill with a bit of mesquite or alder. Put the cover on the grill, adjust all vent to wide open, and let 'er rip for about ten to fifteen minutes. Remove the pan, and put the pizza onto a suitable dish and serve it up. I'm telliing you what; That's some great pizza. I'd put it up against any brick-oven pizza on the planet.
You want pulled pork in a pinch? Place a 4 lb. Boston Butt roast into a slow cooker set on low cooking (not warm) and let it cook while you sleep at night and go to work the next day. When you get home, fire up the grill. Transfer the roast to your sargest CI pan and shred it with a fork. Add yoru favorite flavoring wood chips to the charcoal and put the pan on the grill. Cover and adjsut the vents to about 3/4 closed. This will cool the fire and trap the smoke. Stir the meat after 5 minutes or so and repeat. Cook another 5 mintues and remove from the grill. Add a ladle-full (about 3/4 cup) of the juices from the slow cooker back into the meat. It has to be very juicy. Serve this smoky, wonderful stuff with a couple of barbecue sauces on whole wheat hoagies or whole wheat hamburger buns.
You can make phenomenal coblers and cakes in CI too. Pancakes are a no brainer. I don't think I could make a proper rack of ribs in CI, though it works great for holding a crown roast in the oven.
Seeeeeeya; Goodweed of the North.