Joan, I go to sleep sometimes BEFORE 10, so see it's not just Irvine.
Very glad you reminded me of this topic howevah: There is a new 24-hour resource.
Corky's in Ladera Ranch at Crown Valley and Antonio over by the faux retro Arco station, is available.
On their website they say they make everything from scratch, which, having eaten there, is a little hard to believe, but perhaps some or most is.
Not to damn with faint praise or nothin', but I think it's a tremendous step up from Denny's, say, and certainly something of an island in its area.
Good frites, VERY good onion straws. Huge, far too huge, servings, so order accordingly, I would advise.
The main thing:
24 HOURS.