Before Liang's Kitchen closed, the 99 Ranch-anchored plaza had what I estimate to be at least four restaurants serving nou riu mian (braised beef noodle soup) and fried scallion pancakes. Some of the noteworthy ones: Lao Dong and 101 Noodle Express. Across the street, there's A&J.
Now there's one more. Wei Shian Noodles serves not just beef noodle soup and scallion cakes, it does just about everything else the other beef noodle joints do, including rolling those scallion cakes up with meat into the pseudo-burritos I've talked before when I reviewed 101 Noodle Express.
If this were Little Saigon, these restaurants would all be pho joints; but this is Irvine, OC's undisputed nou riu mian capital.