1Heat oven to 375°F. Line cookie sheet with foil. Place sweet potatoes on cookie sheet; prick several times with fork. Bake 1 hour or until very tender. Let stand 15 minutes.
2Cut potatoes in half lengthwise; scoop pulp into large bowl. Mash pulp well. Add butter, syrup, orange peel, orange juice and salt; mash well. Garnish with rosemary sprig.