Preheat the oven to 375F. Place the pork in a baking dish. On a cutting board, mince the rosemary, garlic, and salt together to form a paste. Rub the rosemary mixture all over the pork. Pour the stock into the bottom of the baking dish, and drizzle the tenderloin with the olive oil.

Roast for 30 - 45 minutes until an internal thermometer reads 150F. Tent the pork with foil and let rest for 15 - 30 minutes. Slice into medallions, and sprinkle the pomegranate arils all over the pork before serving.