Preheat oven to 350 degrees. Cut the vanilla bean in half and scrape out the seeds. Combine seeds with truffle oil and vegetable oil. Run vanilla/truffle paste all over duck skin. Season with sea salt and white pepper. Roast in oven, breast side up, for 1- 1 1/2 hours...or until thermometer placed in leg reads 170 degrees. Baste every half hour. Let rest 15 minutes before carving. Mix pan juices with sage and flour to make exceptional gravy.