Layer sweet potatoes in a 3-qt. slow cooker. In a large resealable plastic bag, combine 2/3 cup flour and seasonings; add chicken, one piece at a time, and shake to coat.
In a large skillet over medium heat, cook chicken in butter for 3 minutes on each side or until lightly browned. Arrange chicken over sweet potatoes.
Place remaining flour in a small bowl. Stir in the soup, pineapple juice, brown sugar and orange peel until blended. Add mushrooms; pour over chicken. Cover and cook on low for 3-4 hours or until meat is tender and potatoes are tender. Serve with rice. Yield: 4 servings.