Ignacio Lopez has more than 30 years of experience working in Bay Area restaurants, so when he says his tacos and burritos at El Taco Factory are the best of the Bay, he knows what he’s talking about.

“Well, no one has proved me wrong yet, but they’re welcome to try,” said Lopez. “Everyone loves our super tacos. We have burritos, quesadillas and nachos too, but the super taco is what keeps them coming back.”

A lot of Mexican restaurants offer super tacos, but the ones you’ll find at El Taco Factory in Brentwood are unlike anything you’ve seen. The label “super taco” is an understatement. The taco is so packed with fresh ingredients that it needs two corn tortillas to hold the meat, melted Monterey Jack cheese, whole beans and salsa fresca. It might take you a while to work your way through the entire thing, but each bite is to be savored, as the meats are marinated overnight in a homemade sauce to guarantee explosions of flavor with every bite.

Ensuring quality food is only one of Lopez’s keys to success. Customer service and a clean and safe workplace are the other ingredients that have kept El Taco Factory thriving since it opened five years ago. This Sunday, Lopez and his team will celebrate their milestone anniversary.

“Honestly, I wasn’t sure if we’d make it this long,” Lopez said. “I’ve watched businesses come and go in this center over the years, but our customers keep coming back and we owe all of our success to them. We have such loyal customers and it’s been a pleasure serving them.”

Lopez said he doesn’t have any special plans for the five-year anniversary. It’ll be like any other day. He’ll come in hours before the restaurant opens to prep the kitchen and get the food going so that everything is ready to go once the doors open. The job requires long hours, but Lopez said seeing the customers walk out satisfied is what makes it all worth it: “When I see a customer walk away with a smile on their face, that’s all I need. It keeps me going. I like to see my customers happy, and when they come back, I know I’ve done a good job. I have some customers who come in several times a week, and I know exactly what they want. They walk in the door and I start their order. It’s loyal customers like that that keep me going.”

Since El Taco Factory specializes only in tacos, burritos, quesadillas and nachos, Lopez offers a variety of meat options so that customers can try something new each time they come in. El Taco Factory’s menu offers eight meats, including carne asada (steak), pollo asado (chicken), lengua (beef tongue), cabeza (beef cheek), pastor (spicy pork), carnitas (braised pork), chorizo (Mexican sausage), and chile verde (pork in a green chile sauce). The prawn quesadilla, El Taco Factory’s seafood option, includes a large grilled flour tortilla stuffed with tiger prawns. The menu features a prawn burrito as well.

El Taco Factory also recently added tortas, Mexican sandwiches, to the menu. Tortas are served with your choice of meat, tomatoes, onion, guacamole, sour cream and salsa fresca. It’s the first new addition to the menu since El Taco Factory opened, but Lopez said he doesn’t plan on making any other changes just yet. “We keep it simple,” said Lopez. “I thought about trying something new (with the tortas) and people seem to like it, but nothing beats our super taco. That’s been our number one from the beginning and I don’t think that will ever change.”

El Taco Factory also offers catering services. A complete list of the catering services is listed on the restaurant’s Web site, www.eltacofactory.com.

El Taco Factory, located at 6660 Lone Tree Way in Brentwood, is open from 10 a.m. to 9 p.m. Monday through Thursday; 10 a.m. to 10 p.m. Friday through Saturday; and 11 a.m. to 8 p.m. on Sunday. For more information, call 925-513-0080.