Forget the cocktails -- last night, they were serving up beef in Andy Cohen's Clubhouse.

Lil' Kim and MSNBC's Willie Geist stopped by the Watch What Happens: Live set. There was flirtation and laughter galore, until Willie hijacked Andy's hosting chair for a second -- because he "couldn’t control himself" -- to ask Notorious K.I.M. some very specific questions.

Willie asked Kim, "What did you think? You were watching the Grammys I assume on Sunday night -- what did you think of a performance by a certain, um, hip-hop artist who kinda rips off your style, if you don't mind me saying?"

The audience went nuts, whoa-ing and oohing knowingly. Kim has accused Nicki Minaj of ripping off her Harajuku Barbie style, while Nicki thinks Kim should have been friendly to her as a fellow emcee instead of calling her out in the media.

Kim laughed and tried to play off Willie's query, innocently saying, "I don't even know -- Who?" to hoots and applause.

Andy confessed to Kim that he'd been flooded with viewer questions for her about Nicki, asking "How do you feel about Nicki's song 'Stupid Hoe' (which some say is a swipe at Lil' Kim)?"  At that point, Kim's tact vanished, and she said, "I'm pretty sure I feel that same way everybody else feels right about now," to the crowd's delight.  She smiled and giggled a bit as she let her true feelings show:  "If you have to make a song called 'Stupid Hoe,' you must BE a stupid hoe."

See the moment for yourself.