I don't know if someone already stated this one with Jhun and Cool Choi. I really can't verify if it works on all the characters{like Bao, Choi, and Chin}.
You need to be in the corner, then the opponent has to do the a+b roll toward you. If you time it right, you can do the back,back, down b{hop back and step} call Cool Choi, you will notice that if you hit the opponent as he is rolling toward you, when you are hopping back, your Jhun will fly forward, Cool Choi, hits the opponent as you are flying forward, you bounce off the opponent, now this is the tricky part, depending on where you are, you may either step again{hopefully you are, in a position, where you can stomp the opponent again, then execute the qcfX2d super) sometimes you end up bouncing off the opponent and going backward. I really don't know how to use Jhun's stances and stuff, but to do this combo, you must rely on a whole of circumstances, that only occur once in a blue moon, and I do not suggest even trying it unless you are willing to lose a few matches doing so. I promise you, it is a somewhat nice combo{because of how hard it is to do}, to perfect it, it takes a lot of work and money.