No, never even heard of it; it has to be newish.
Well, they were in Villa Park years and years ago, but put in a drive-thru restaurant in 1960 in Downers Grove (where I grew up).
The first Portillo’s sit-down restaurant did not open in downtown Chicago until 1994 at Clark and Ontario.
Sorry, you missed out on some good fast-food eats! :) They have them in other states now as well.