Mince the ham and mix with the breadcrumbs and potatoes. Place in a small pan and, heating gently, bind with the beaten egg and white sauce. Season well and spread on a plate. Divide into 12 equal portions and leave until cool. Shape into croquettes, coat with egg and breadcrumbs, and fry until golden brown in deep fat. Drain, sprinkle with paprika pepper and garnish with parsley.