It seems like every Mexican restaurant on the planet bills itself "authentic." Maybe most of them really are authentic, if by that you mean possessing yellow walls and serving Corona.

But really, truly authentic? That slippery term can be interpreted many ways, and applied equally to traditional regional varieties of Mexican cooking and to the cousins, each distinct, that flourish north of the border in places like California, New Mexico and Texas.

My own tastebuds were trained on years of cheddar- and beef-enhanced Tex-Mex, and later refined in Texas restaurants that aimed for the less extravagant dishes more common in Mexico. It is a fondness for the latter that has turned me into a regular at Hadley's Mi Tierra, an unassuming place behind a row of shops and the Knights Inn on Route 9.

Owner Jorge Perez began Mi Tierra as a small addition to his grocery business, but the restaurant proved such a hit that the grocery part of the business has gradually been eclipsed—now the space is 100 percent restaurant.

Mi Tierra's menu (about to undergo expansion, it's worth noting) was created by the extended Perez family, who originally hail from Guerrero, Mexico. The menu is sizeable enough already that exploring all its offerings takes a while, but a few standout dishes are so reliably tasty that it may prove difficult to bring yourself to choose others.

Burritos have long taken center stage as the standby of American incarnations of Mexican cooking, and Mi Tierra's burritos are enormous meals (even multiple meals) in themselves, full of the usual list of meat and/or vegetable stuffings. The piece de resistance arrives with the topping of crema and grated cheese.

Mi Tierra's tacos offer plenty for the seeker of familiar comforts, too. The filling arrives on handmade corn tortillas, and the simplicity of the dish belies a real wallop of strong tastes. The chicken tacos, for instance, contain only chicken, onion and cilantro, but arrive with a lime wedge and a dish of salsa verde. Put all of that together, and the marriage of tastes is deeply satisfying.

Beyond such standard fare as burritos and tacos, you'll find plenty of substantial choices from familiar to more unusual.

Mi Tierra's enchiladas arrive in the fashion more commonly seen further south, covered in cheese and swimming in sauce rather than topped with a meager helping of it. Two varieties of enchilada sauce in particular—verde and mole poblano—offer complex tastes and pleasant spice.

Wander further off the beaten path and you'll be plentifully rewarded. Even as a veteran devourer of Mexican food, I had never seen huaraches. Though they qualify as "antojitos" (more or less "little snacks" or appetizers), at Mi Tierra, especially with the addition of a side of rice and beans, they are more than enough for a whole dinner. Huaraches are in the neighborhood of tostadas, but instead of a crisp-fried tortilla, they employ a thick version of a corn tortilla as a foundation. Those tortillas are the stars, chewy and redolent of the grill and lime-soaked corn masa flour. They are topped with combinations of chicken or steak, beans, lettuce, cheese, verde sauce and crema, and the result is rather like a taco turned up to 11.

Turn your attention to the even less usual, and you'll find a section of Mi Tierra's menu called "Platos Tipicos" ("typical plates"). There treasures lurk like bistec con nopales (steak with cactus strips), chicken breast in mole sauce, and several versions of shrimp served in sauce. The most dramatic presentation on offer is shrimp served with garlic slices and pieces of dried pepper, although the dryness of the peppers makes them better as decoration than dinner. On the other hand, the shrimp in chipotle sauce is a real eye-opener, probably the spiciest choice at the restaurant. All the platos tipicos arrive with a side of two handmade corn tortillas, and allow for a particular strength of good Mexican food: not only do the sauces mix and mingle with the rice and beans, any combination of the ingredients can end up wrapped in one of those tortillas to create a unique package of flavors.

I don't know precisely where Mi Tierra falls on the grand, unfathomable Mexican restaurant scale of "authentic," but I do know I've done much worse even in Texas. The Perez family recipes make simple ingredients sing with spice and just-right combinations. That, in the end, is the necessary formula for creating great dishes in the context of an old cuisine anchored in basic ingredients, and it's plenty authentic for me.