Brock by big punch knockdown, followed by a "no intelligent defense" stoppage due to GnP. Kongo pressed against the fence still managed to buckle Cain at least 2 times, as I remember it.. Im betting that if Cain catches one of those lunchboxes, it wont go well for him.
Cain's best shot to win this fight is to literally chop the champ down. Repeated leg kicks at the end of punch combo's will slow brock down, and take a lot of his power away. Once the leg kick is established, and Lesnar starts lookin for it, a head kick or a good takedown situation should open itself up for Cain, if he can be in a position to capitilize on it.
Also Mir needs to beat someone a little higher on the ladder then cro-cop to earn himself a title shot, Id say. A rematch with Nog, or a fight against JDS would be a lot more convincing..