Season both sides of the pork with salt and let rest for 30 minutes. Then use a paper towel to pat pork dry; rub with Chicken and Rib Rub.
Heat the oil in a cast iron over medium - high heat. When the oil is hot, add pork. Cook until golden, about 3 - 5 minutes.
Flip pork and cook for about 1 minute. Reduce heat to low and cover with a lid. Cook for 6 - 8 minutes or until thermometer reaches 145 F.
When pork is cooked, add in butter and once melted pour over pork. Remove from pan and let rest for 10 minutes before serving. Serve with pan juices poured over top.