This work presents an improved microwave multimode cavity for porcelain table- ware sintering. It includes 6 magnetrons, each one with a nominal power of 1 kW at 2.45 GHz. The distribution of the electromagnetic field inside the cavity is calculated using the COMSOL Multiphysics software. The improved automated control system comprises the use of a pyrometer that allows the analysis of the thermal delay between the temperature given by a thermocouple and the real temperature in the porcelain material. Results exclude the existence of the so-called non-thermal microwave effect, recognized in some literature. Physical properties, such as den- sity, rupture energy and impact resistance, are compared with those of tableware obtained by conventional methods. The improved microwave oven allows a better temperature measurement, with a faster sintering with the same quality standards than the conventional sintered porcelain.