I have too many to pick one favorite so here's a list:
Kaju Soft Tofu in GG or Buena Park. Don't go to the one on Walnut in Irvine.
Hanyang for Korean soup in Buena Park.
Sababa Falafel Shop in GG.
Mo Ran Gak for KBBQ in GG.
Sookdal for KBBQ (specifically pork belly) in GG.
Nok's Kitchen for Laotian in Westminster.
Sushi Murasaki in Santa Ana.
Los de Juarez Burritos in Anaheim.