Gaga and Ashanti ended up on stage together late Saturday night after Mother Monster wrapped up her "Enigma" show at the Park MGM Las Vegas.
A small gathering went down afterward at the NoMad Las Vegas, an exclusive hotel within the Park MGM.
Musician Brian Newman was performing, when Gaga took the stage and immediately commanded the attention of the small crowd.
Gaga first toyed around with resident burlesque dancer, Angie Pontani, by stripping her clothes off.
She then got a hold of the microphone and was joined by Ashanti as the two crooned on stage while the house band laid down a smooth beat.
Ashanti was in Sin City performing at the Orleans Arena for radio station Q100's "Nightmare On Q Street" concert.
After singing for the crowd, Gaga and Ashanti could be seen dancing and talking, and the Oscar winner even twirled the R&B around!
They also took selfies together, and it was pretty clear Gaga was in her element.
Fans of Gaga and Ashanti immediately gushed over the collab, and clamored for something official between the two.
"I’m so heated I missed this!" one fan wrote, while another declared, "I’m Herrrre For Ittt!"
She also seems to have fully recovered from that nasty accident last week when a fan picked the star up and dropped her off the stage.