Invited presentation: Kernel fuels have emerged as promising candidates for high temperature gas reactors due to their robust nature and exceptional tolerance at elevated temperatures. Their potential application in space systems has attracted significant attention from developers. Collaborating with the NNL, Bangor University is engaged in the advancement of a diverse range of candidate fuel systems. Leveraging novel manufacturing techniques and state-of-the-art computer modeling, our research aims to optimize the performance of these fuels. One area of focus is the integration of burnable absorbers within the UO2 and UCO kernels themselves. Our investigation includes an exploration of phase segregation, variations in thermal conductivity, and the impact of processing parameters, all of which are crucial for enhancing fuel performance. Moreover, our efforts extend to the development of manufacturing methods, complemented by optical dilatometry and simultaneous thermal analysis. These techniques enable precise calibration of sintering parameters, facilitating the refinement of fuel properties and performance.