Post [Q] Installing A new Rom

Hey guys, I've rooted my phone and started to tinker with the software of my Samsung Galaxy Y. I am running Hyperion Final build and the latest merruk kernel. I am planning on installing the Jellyblast rom for galaxy y. I wanted to know whether we have to be in stock rom and kernel to flash a new Rom? For example, for me, running Hyperion Final build, should i flash the stock Rom and kernel both and then flash the Jellyblast rom? or just flash the Jellyblast?