Heat butter and oil in large skillet over medium-high heat. Season pork with salt and 1/8 teaspoon pepper. Add to skillet; cook 3 to 4 minutes per side or until internal temperature registers 160°F.
Remove pork to platter; keep warm. Add port to skillet; cook 1 minute, scraping up any browned bits from bottom. Add broth, ketchup, remaining pepper and thyme; cook 3 minutes, stirring occasionally.
While cooking meat and sauce, prepare Parmesan Potatoes.
Serve pork with Parmesan Potatoes. Spoon sauce over pork and potatoes.
Prepare instant mashed potatoes according to package directions for 4 servings. Add minced onion to liquid. Stir in Parmesan just before serving.