I grew up in southern California, lived for years in Oregon and LOVE Mexican food. My favorite is usually off of trailers because of the authentic flavors. Since moving to Costa Rica I had pretty much given up on good Tex Mex as a regular thing. But NOW, each trip to San Jose/Alajuela is an excuse to go to Jalapenos Central. Norman and his staff provide an very very good meal at a ridiculously low price and the BEST customer service of any restaurant I've been to recently. It aint faincy, but it is fresh, delicious, and full of traditional flavors and textures.
Do not miss the Sopa Azteca (sometimes called Tortilla Soup in other places), it is the BEST I've ever tasted. Also, LOVE the hot sauce they serve on the side. Lastly, the chicken enchilada is is simple but delicious!