1. Remove any excess skin from the turkey breast, leaving only enough to cover the top and sides. Rinse the turkey with cool water, and pat dry with paper towels. Place on a rack in a roasting pan.
2. Combine the basting sauce ingredients in a small bowl. Brush half of the sauce over the top and sides of the turkey breast, and reserve the remaining half for later use. Pour the wine or sherry into the bottom of the pan. Cover the pan with aluminum foil, crimping the foil around the edges of the pan to seal.
3. Bake at 325°F for 1 1/2 hours. Carefully remove the foil (steam will escape), and baste the meat with the remaining sauce. Bake uncovered for an additional 45 minutes, or until the skin is golden brown and a meat thermometer inserted in the breast registers 170°F.