Add: In SoCal go to El Pollo Loco, Super Mex, Rubio's, and Whahoo's. El Pollo Loco started in Mexico, but is "American" now. The other three are SoCal based; the latter two based mainly on fish tacos.
As a SoCal native, Mexican "style" food is my favorite diet. Mix them up. Cal-Mex; Tex-Mex; Mex-Mex, Surf-Mex...just hurry up and serve!! How about Arizona-Mex?
Had to eat dinner. LOL
We don't do a lot of fast food, but our favorite Mexican restaurant is family-operated and is called Casa Molina's. Cheese crisps with guacamole that are exquisite.