A process is disclosed for heat carrier generation for the advanced cracking reaction process comprising separately preheating an oxidant stream; joining a fuel stream and at least a portion of the process steam stream to form a stream having a steam-to-fuel ration between 0.1-10; preheating the joined stream; reforming said joined stream at a temperature up to 1000.degree. C. in the presence of a reforming catalyst comprising at least one metal selected from the metals of Group VIII of the Periodic Table of Elements on an inert support; separately preheating any remainder of the process steam; and mixing said preheated oxidant, joint and steam streams to burn in admixture in a combustion zone to provide a hot gaseous combustion products stream.