"Keep fucking that chicken" (KFTC) is a phrase coined by television anchor Ernie Anastos during a live broadcast of the Fox 5 New York local news. It is presumably a phrase of encouragement similar to keep on truckin
, only with a more pronounced and colorful air of defiance.
The chicken being fucked may be an actual chicken, could be pejorative slang for a woman (i.e. chickenhead
), or some other metaphor for an object of desire or enjoyable activity. In any case, KFTC seems to be a gesture of support to the recipient to continue doing whatever it is that they're doing, despite what others may say, so long as it makes them happy.
Adam: I could be making more money at another job, but I like the work I'm doing now.
Bob: Whatever, keep fucking that chicken.