A little-known Mexican-food chain run by a former Chipotle exec is ranked best in America

Rubio's Coastal Grill is the David to Chipotle's Goliath.

And David is winning.

Rubio's, a San Diego-born chain founded by a college-aged surfer and made famous for its fish tacos recipe, toppled Chipotle to take first place in the Mexican category in a Consumer Reports survey earlier this year.

The Baja California-inspired chain, which serves tacos, burritos, bowls, and other seafood fare, has 163 restaurants scattered on the West Coast. Chipotle, in comparison, has nearly 1,700 locations across the US.

We visited one of Rubio's recently renovated stores in Valejo, California, to see what the buzz is about.