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Ballston has long been a destination for Mexican food. The Rio Grande Cafe—perennially included among the Washingtonian’s 100 Very Best Restaurants—is there, at the corner of Fairfax Drive and Taylor Street. A few blocks away, in the Ballston Common Mall, sits a newly opened Chevy’s, whose ads emphasize the freshness of its south-of-the-border favorites. Both of these places fill up in the evenings with 20-something workers from the look-alike office buildings that line Wilson Boulevard and threaten to consume what remains of an old working-class neighborhood. Both restaurants have loud, festive atmospheres fueled by frozen, sweetened tequila and imported beer. Neither has the area’s best Mexican food.

Glam-Mex cuisine, as dished out by these and other upscale cousins of Taco Bell, may have its pleasures, but the real thing is both harder to find and better. Glam-Mex is an unmitigated assault on the senses—sauces that are simultaneously too sweet and too hot, processed cheeses designed to dominate rather than harmonize in a dish, a mix of cold iceberg and hot meat, crunch vs. mush. The food has the virtue of being easy to prepare; the same small palette of ingredients is churned into nearly everything on the menu. The predictable drawback is that all dishes are nearly the same, distinguishable only by shape: “I’d like a shell-and-tube combo, please.” Authentic Mexican food has finesse. It’s better balanced; it can even, on occasion, be subtle.

And it’s often hiding in plain sight. Las Tunas, at the corner of Wilson Boulevard and Pollard Street—across from Indian Spices, Gifts and Appliances, another Arlington culinary landmark—is the sort of place you could drive past daily for years without paying much attention to. A small, free-standing restaurant with a rarely full seven-car parking lot, Las Tunas has been serving Mexican as well as Salvadoran specialties for almost seven years, and it’s the place I go when I crave the real thing.

Las Tunas is nothing if not low-key. Tourist-trade souvenirs contribute to a rec-room atmosphere. A television over the small bar (beer only, served in bottles) is constantly on, usually tuned to soccer or Spanish-language soap operas. A few

settled-in pals are usually talking quietly on the bar stools near last year’s babe calendar, put out by a brand of beer that is no longer carried—if it ever was. The bartender/waitress, who can often serve the restaurant’s three small rooms with plenty of time to spare, is friendly and chatty. And Las Tunas is one of those places that always seem cool and dark, despite its lack of AC and its large windows. It clearly does a fair amount of bar business, but the big draw is the kitchen.

Purists may scoff at Las Tunas—both for its Salvadoran menu and because it doesn’t serve hard-core favorites such as tripe tacos—but the Mexican food on the menu is better because the cooks mind the fundamentals. Take the frijoles: Las Tunas treats this staple with respect. At the restaurant’s more upscale neighbors, the beans are an obligatory puddle of decoration with a protective layer of processed cheese melted on top; at Las Tunas, the beans are worthy of their small, precious portions. Positively chocolaty, with a velvety texture and deep earthy flavor, they’re worth the trip by themselves.

And instead of the cheddar or jack favored by most glam-Mex places, Las Tunas uses a softer and milder quesa blanca, which adds creaminess to entrees without imparting an unwanted tang. The tortillas are crisp, with the real flavor of corn, and each dish is allowed to have its own character. The chicken quesadillas on the appetizer menu are enlivened by the fuller flavor of dark meat, and the delicate sour-cream-based sauce that accompanies them has a hint of goat cheese, which adds unexpected complexity to what is usually a bar-food-caliber snack. Charcoal-broiled beef, marinated in a fruity sauce and then practically caramelized, dominates Las Tunas’ soft tacos, which are double-wrapped and dressed up by a bit of fresh tomato and green-leaf lettuce. The result is a simple and gratifying balance of bitter and sweet.

Even that gringo favorite, fajitas, is handled with aplomb. In the glam-Mex world, fajitas are usually more sizzle than steak (so to speak), but Las Tunas turns them into something more substantial. The customary fry pan is brought to the table still hissing with onions, green peppers, and perfectly cooked shrimp. (Steak and chicken versions are available, too.) A multifaceted dish, it could be served on rice or noodles and be just as good—even without the dubious amusement of self-assembly. The sauce is both peppery and sweet (I suspect from canned tomato paste) but nonetheless satisfying. Unfortunately, it’s served with a single flour tortilla cut in half, which isn’t nearly enough to wrap the large, shrimp-heavy portion.

When in a homier-looking place, my wife, Jan—who thinks me too trusting—is likely to elbow me and warn against ordering fish. She has doubtlessly saved me from many bad meals, but, at Las Tunas, her concerns would be misplaced. The restaurant has many fine seafood meals, mostly on the Salvadoran side of the menu. The shrimp dishes are all excellent and generously portioned. My favorite is camarones en crema, which features the crustaceans in a browned cream reduction with onions. The sauce is nutty and robust but doesn’t compete with the more subtle flavor of the shrimp. The pescado frito is a whole white bass, sizzling straight from the deep fry, with a crunchy, somewhat corny-tasting skin and moist flesh.

In general, the Salvadoran food makes a more elegant presentation than the Mexican dishes. Las Tunas’ version of the tamale appears on the Salvadoran appetizer list, and it’s not the usual one-piece cake of corn and meat. The filling is baked and presented in a husk but has not been compressed as in the Mexican version. Instead of being finger food, these creamy, polentalike tamales demand to be eaten with a fork. The side of pork can be a little dry but is infused with an agreeable steak-joint-grilled flavor. Served with sour cream and jalapeño relish, the dish reminds me of the sort of complex little appetizer found at trendy downtown restaurants rather than at neighborhood joints.

Missteps, however, do occasionally occur. The sopas de res, for example, described benignly enough as a homemade beef soup with vegetables, indeed boasts an unmistakably homemade broth, but the odd assortment of stuff floating in it—a quarter of a plantain with the peel still on, a half a cob of corn, a piece of yucca, a few cut short ribs with little meat on them—is bewildering. It doesn’t really add up to soup; it’s just a weird little buffet in a bowl.

The sopa de mariscos, however, is not only much better but also something of an experience. In a peppery chicken stock, shrimp, clams, a whole crab, and a section of bass, along with cilantro, green peppers, onions, and tomatoes, somehow come together into a surprisingly vigorous whole. It’s also a challenge to eat—all the more so because the waitress is liable to leave you with only a spoon to attempt it. It is possible to break open a crab claw with this single tool, but don’t try it while wearing your best shirt.

Some of the restaurant’s roughness is surprising. It’s a truism that good food takes good time, but Las Tunas’ kitchen sometimes requires that and a seemingly interminable amount more, particularly if the order is large or varied. Menu descriptions are not always accurate—a dish might be served with salad rather than the promised vegetables—and on one visit, a passing group’s request for a takeout menu has to be denied because the restaurant has run out.

On the other hand, over at Rio Grande, the crowds are often overflowing well past capacity (or at least comfort); at Las Tunas, you’ll never be denied a table.

Las Tunas, 3902 Wilson Boulevard, Arlington, (703) 807-0126. —Jandos Rothstein

Eatery tips? Hot plates? Send suggestions to hungry@washcp.com. Or call (202) 332-2100, x322.