Solid-state ceramic electrolytes are a crucial component of solid-state batteries, however the processing conditions for these ceramic materials is challenging requiring elevated temperatures during sintering to produce suitably dense layers. As solid-state electrolytes (SSEs) start to reach market there is an increasing drive for faster and more energy efficient sintering methods, especially methods that can reduce the volatilisation of lithium during typical sintering. In this talk we present the result of two different advanced sintering methods, cold-sintering, and flash-sintering, on the oxide SSE aluminium doped lithium lanthanum zirconium oxide. The contrast between these two methods is compared through examination of the sintered ceramics microstructural features by scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. The optimisation of both methods is discussed in detail such as the effect of pressure, temperature, solvent quantity and time during cold-sintering, and the effect of furnace temperature, current profile, and various electrode configurations during flash-sintering.