Deep within the psyche of every Texan is a primal memory of the quintessential Mexican dinner. For my generation—growing up in the fifties and sixties—that was a combo platter (“Hot plate! Hot plate!”) with a pair of oniony yellow-cheese enchiladas, a crispy taco, a sodden tamale, refried pinto beans, Spanish rice, corn tortillas in a cute sombrero-shaped basket, and a pecan praline or sherbet for dessert. Of course, there were regional differences (I have friends who never ate corn tortillas, only flour), but the broad outlines were all but universal. Fast-forward thirty years to the present, and the picture becomes vastly larger with quesadillas, black beans, pico de gallo, tomatillo sauce, chiles rellenos made with poblano peppers, sizzling piles of fajitas, tacos for breakfast, and flan for dessert.

Mexican food in Texas, once monolithic, is all over the map, and if you think it’s different now, just wait. Some of the little taquerías and cafes I visited traveling around the state were exactly like those I went to in Texas’ sister cities across the border. I felt like I was in Mexico. And the food—amazing: In Fort Worth I had a chicken tamal cooked in a banana leaf, in San Antonio a heavenly salsa made with roasted morita chiles, in Houston a torta de lengua (a sandwich of spicy beef tongue on a crusty bolillo), and in Dallas quesadillas of huitlacoche (smoky-flavored corn-ear fungus). Are such dishes and such restaurants everywhere? No, but consider this: A dozen years ago they were all but nonexistent.

The border is moving steadily north, and as it does, the Mexican food in Texas is becoming more like the Mexican food in Mexico. Immigrants arrive, they open shops and restaurants, and their food ways mingle with ours. But if Mexican food is changing from the grassroots up, it is also changing from the top down. In a handful of restaurants—mostly upscale places like Austin’s Fonda San Miguel, Dallas’ La Valentina, El Paso’s La Norteña, and Houston’s Taco Milagro—tradition is being tinkered with. At these places you can find a traditional mole infused with a blackberry purée or a “reverse-taco salad” with crisp vegetables and tortilla strips wrapped in lettuce leaves. Inventive chefs and owners have made it a personal mission to bring cutting-edge Mexican cuisine to their customers. Texas will never be Mexico, nor would we want it to be. No. 2 dinners are part of our heritage. But change and diversity are good, especially for putting things in perspective. On more than one occasion, I opened a menu to find the majority of it devoted to interior dishes and only a small section labeled “Tex-Mex.” In this context, I began to see Texas’ Mexican food for what it has always been: the regional cooking of an orphaned Mexican colony. As our Hispanic population grows, more change is on the way. The Hispanic Century, with its vibrant culture and music and food, is at our door.

Each restaurant included in this story is rated on three things: its guacamole, chips, and salsa. The scale used is 1 to 5, with 1 being poor and 5 superior. A perfect guacamole is made with freshly mashed avocado, onion, tomato, lime or lemon juice, and salt. Jalapeño, garlic, and cilantro are desirable but optional. (Along both sides of the border, guacamole is usually plain mashed avocado. I gave that style a 3—good—and awarded extra points if other ingredients came with it.) Perfect chips are crisp and almost greaseless. Perfect salsa varies depending on the type, but it always has a robust flavor and moderate heat.

Statement of full disclosure: I happen to prefer interior Mexican food to Tex-Mex. I also tend to go for either very low or very high—little diners and taquerías or fancy-schmancy places with high prices. Chains and middle-of-the-road mass feeders aren’t my cup of caldo. So if your favorite place has a name like Los Sombreros de los Amigos Locos and autographed pictures of celebrities and football players on the wall, you may not find it here.

Now if you’ll excuse me, I have to go apply to the witness-protection program.