In the future, mass production of ceramics using ULES is expected to provide a significant breakthrough in establishing a greener manufacturing route, while opening the door to new materials and applications. The exponential growth of research into ULES is expected to support the development of a wide range of functional materials; this can only be achieved by understanding the triangle of processing-microstructures-properties. Materials properties can be tailored at the grain boundary level by identify a suitable liquid (‘a sauce’) able to engineer chemical composition, grain boundary mobility and degree of crystallisation.