Coral Beach Cantina is right off PCH before Zuma Beach. I love this place! It's casual, you can eat inside or ouside. It's not too expensive, meals are around 5-10 dollars.
Service is pretty good, meals come out fast. They serve chips and salsa before you order: a MUST for any Mexican restaurant.
The food is delicious and portions are hefty. I usually get the chicken quesadilla and end up taking half of it home every time.
It's right next to Zuma Sushi. You have to make a U-turn if you're driving towards Zuma.