If using powered gelatin, sprinkle it on 4 tablespoons of the milk in a small bowl. Stand basin in very hot water until gelatin dissolves. Heat the remaining milk with the rose water and sugar and add gelatin. Stir gently until sugar dissolves. If using leaf gelatin, soften in water for a few minutes before adding to milk and stirring until dissolved. Pour into flat dish and leave to set. Turn out of the dish and cut into lozenge shapes. Decorate with sugared flowers, or, if you wish to impress, edible gold leaf.