CHICAGO, Oct. 06, 2026 (GLOBE NEWSWIRE) -- Portillo’s fans know the brand’s famous chocolate cake and cake shakes are simply out of this world. Now, as spooky season gets into full swing, Portillo’s is teaming up with the OREO brand to introduce a trio of new treats: the OREO Shake, OREO Cake and OREO Cake Shake. Available nationwide for a limited time starting October 6, this iconic collaboration gives guests even more flavor-packed menu items to complete their favorite Portillo’s meal.