So as to provide, with high accuracy, an actuating variable for actuating a torque control element in an electric vehicle steering system and achieve this with reduced complexity as compared to the known methods and devices, an actual torsion-bar torque (MD) is detected, a differential torque is found from a predefined target torsion-bar torque (MD,ref) and the actual torsion-bar torque (MD), and the actuating variable is determined by means of an output feedback controller, as a function of the differential torque.