Preheat oven to 325 degrees F. Melt the cube of butter. Pour melted butter all over pork tenderloin.
Then in a small bowl mix the meatloaf seasoning packet with the parmesan cheese. Pour mixture in baking dish. Roll the buttered tenderloin in the mixture until well coated. Score the entire pork tenderloin with a knife approx. 2 inches apart.
Place the seasoned tenderloin in the oven for about 1 hour 45 minutes.