It's Cuz Your Black
A saying that is said everyday usually in a non-racial (most of the time) way, this quote is used just to mess around with your black friend, but may still get mad because you said it, however this is a very popular catchy phrase that should get said at the right unexpected moment, and is usually always funny if used at the right time and not exaggerated.
Leondre: Yo Izzy.. I didn't get the job at pizza hut..
Izzy: It's cuz your black.
Izzy: It's cuz your black.