The LA area has terrific Mexican food restaurant chains, and Baja Fresh is definitely one of the more prolific: There are many locations all over town.
This South Pasadena spot in the Vons Shopping Center is spacious and closes fairly late. Its a decent night dining option versus a full-service place or a drive-thru.
As the name of the chain goes, its food is impressively fresh but still very affordable. Here again, Mexican restaurants like Baja Fresh are a great inexpensive alternative to fast food.