In 12-inch ovenproof skillet, sear tenderloin over medium-high heat; cook 2 to 4 minutes or until browned on first side. Turn, and immediately remove from heat. Add potato mixture to pan around pork; transfer to oven, and roast 25 to 30 minutes or until pork reaches at least 140°F in center. Remove from oven; transfer pork to cutting board, and tent with foil. Let stand 5 minutes (pork should reach at least 145°F in center after resting); stir potato mixture, and return skillet to oven. Continue to roast 5 to 8 minutes or until potatoes are tender.