Bebe Rexha needs to hit up an old friend, fashion designer Michael Costello, because he tells us he's got the perfect look to show off her sexy curves at the Grammys ... size 2 dresses be damned!!!
We got Michael, who appeared on "Project Runway," outside his store in downtown Los Angeles Tuesday ... and he shared some of his plans to highlight Bebe's curvy figure at next month's Grammy Awards -- pro bono!
As you know ... Bebe -- who just got her first Grammy nomination -- went NUCLEAR on fashion designers who she claims refused to dress her for the awards show because her figure isn't small enough ... telling them she doesn't want to wear their "f**king dresses" anyway!
Michael, who dressed Beyonce when she picked up 3 Grammys in 2014, says he's totally on board with Bebe and all those other designers can "f**k" off!
Watch ... Michael delivers his pitch to dress Bebe, and says he's only one call away.