A hob includes at least one heating zone, a temperature sensor for detecting the temperature of a cookware element placed on the heating zone, and a control unit for operating the heating zone. The control unit is constructed to heat up the cookware element in a heat-up phase and to control the temperature of the cookware element to a target temperature in a holding phase in at least one operating mode. In order to enable an energy-saving simmer operation, the control unit detects a boiling point of the liquid contained in the cookware element during the heat-up phase and determines the target temperature as a function of the boiling point.