My grandmother had cast irons that were so well seasoned that an egg could easily slide around the pan as it fried. I use mine to brown chicken and to caramelize veggies like peppers and onion for fajitas. I've had my cast iron since I first moved out on my own and have diligently cared for it in the pursuit of the perfect season. Needless to say, this can be difficult to achieve. Especially if you live in a home where others may not appreciate the fact that cast iron needs certain care.
My husband knows his way around a kitchen and still I found he had been scrubbing my cast iron thoroughly with soap after every use. This explained the matte finish. In order to restore the pans luster I used an old trick using salt and oil.This method is also a great way to remove rust from a cast iron.
Take a dry pan and add a handful of salt and about a quarter cup of oil. You want to make a paste. Next, take a paper towel and use it to scrub the paste around the pan. As you scrub the salt will turn a dingy color and pick up the rust and other nasty bits. Repeat if you think necessary. Once you feel the pan is clean, simple rinse under hot water and wipe it dry. The pan should remain well oiled and shiny. At this point you can bake it upside down in the oven at 400 degrees for an hour to restart the seasoning process.