The "Bodak Yellow" hitmaker is one of the guest stars making a cameo in the rebooted competition show, in which budding designers try to impress model host Karlie Kloss and mentor Siriano, as well as judges Nina Garcia, the editor-in-chief of Elle U.S. Magazine, and fashion guru Brandon Maxwell, to win a cash prize and have their top creation sold to members of the public.
Cardi's appearance on the new season 17 came after Siriano, who has dressed the rapper for numerous high-profile occasions, called in a favour from his celebrity client.
"We have Cardi. I drag her out to help us," he smiled on U.S. breakfast show "Today".
Her presence on set left Karlie and Brandon in awe, as they had been mimicking the feisty star's quirky "Okurrr" catchphrase to show their approval of contestants' designs throughout the series, before Cardi made her grand entrance.
"That was like, our inside joke, all day!" exclaimed Karlie, as Brandon explained, "Every time we liked something, we'd say, 'Okurrr', and then she showed up!".
"It was amazing," Karlie gushed.
The new season of "Project Runway", which previously featured Heidi Klum and Tim Gunn as host and mentor, respectively, debuts on Thursday, March 14.