Honestly, it's about the stupidest thing I've seen in a while, lol.
It's some young chick on Dr. Phil that's a delinquent. Dr. Phil had trouble understanding her because she talked all stupid-ass street slang. Then when the audience laughed at her, she was trying to say, let's step outside and take care of this. But her dumbass came across like, "Cash me ouside, how bout dah?" As in, "Catch me outside, how about that?"
I don't have any excuse for using it other than it's popular :-)