Tiffany Haddish Entertains Dinner Goers with Impromptu Song & Dance

Tiffany Haddish never passes up an opportunity to put on a show -- and that was certainly the case this weekend during a double date in Vegas ... where she took the building by storm.

The comedian was at dinner Saturday night at Delilah (the Wynn resort one), with none other than her BF, Common, and Chelsea Handler ... who was with her guy, Jo Koy -- all of whom were in attendance, we're told, for a group outing.

There was a live jazz band performing for the guests there, and at one point -- TH felt the urge to get on stage herself and do a showstopping number with the help of the musicians.

Check out this video of Tiff doing exactly that ... performing a cover of Tina Turner's "Proud Mary" to what we're told ended up being a lot of fanfare. Word is ... she got a standing O after, and you can kinda see why. Tiffany's busted a move and got her sing on, big time!

Definitely a cool moment ... but it's far from the first time Tiffany's gotten a hold of a mic to entertain a crowd on the spot. She actually does it pretty often -- we've seen her do a pop-up show during Thanksgiving last year, and even at a Golden Globes after-party in 2020.