Preheat the oven to 375°F. While the oven is heating, mix the paprika, thyme, mustard powder, salt, and pepper together in a small bowl.
Pat the pork chops dry with a paper towel and then sprinkle the seasoning over the pork chops and rub in so that they are coated all over.
Heat a cast iron pan to medium-high, then drizzle in the olive oil and brown the chops all over for about 2-3 minutes on each side, using tongs to turn them.
Put the butter and rosemary into the pan and place into the oven to bake for 12-15 minutes. Scoop the butter over the chops again and let the chops rest for a few minutes before serving.