Fried potatoes and onions was one of the things I most wanted to try in cast iron. My first time was a fiasco. I ended up removing them to my electric skillet to finish them. This time I used baked potatoes from the day before and got the most beautiful golden brown fried potatoes. Start by melting some butter or bacon grease in the skillet over medium heat. I used some of both. Cut the cold potatoes into the skillet. Add salt and pepper. I love onion so I added some onion flavored Mrs. Dash. Watch them closely but give them a chance to brown without being tossed often. This will prevent them from breaking up or turning mushy. Cleaning the skillet was just a few swipes with a paper towel.