The Big One_lowres

The carne asada (right) comes either separately or as part of TAQUERIA JALISCO'S popular gorditas (left).

At the dead end where 19th Street meets Harrison Street in San Francisco, a truck produces the best tacos of my life: greasy kernels of fried pork and tear-jerking salsa verde loaded into warm, double-ply corn tortillas that barely outsize a silver dollar. Chopped cilantro and white onion sprinkled on top fire raw wetness through the spice and grease. You eat these tacos standing up, emergency napkin in your spare hand, no room for a beverage. It's often difficult to gauge in a restaurant, with its variables of service and mood, what role food plays in a meal's success. Analysis is simpler at a truck; the food is either everything, so sublime you gladly forgo civilities like the chair, or it's just a byproduct of convenience and economics.

Like those tacos are to their back-street truck, the gordita is Taqueria Jalisco's everything: a food that could single-handedly create a party on any street corner. A gordita has the soul of a taco but functions like a sandwich. The bread, so to speak, is a puffy corn tortilla made on the premises, its complexion ruddy and coarse-grained. This thick tortilla's outer surface is slightly chippy and shell-like, as if from pan-frying, which is essential for retaining a gordita's sometimes drippy fillings.

A member of my family was shocked to learn that "gordita" does not translate to "a Taco Bell favorite," but rather to "little fat one" or "chubby girl." In order to live up to this definition, the tortilla must be sliced partway open and stuffed to nearly blowfish capacity. Many people are moved to cut the little fatties in half, imagining erroneously that they'll be easier to handle. These are $2.50 taco sandwiches. Don't be a sissy.

Refried pinto beans, sour cream, crumbled queso fresco (cheese) and shredded iceberg lettuce co-star on every gordita, acting as background dressings for whatever meat filling sounds appealing. Gorditas made with carne asada, salty nuggets of charred beef, are fantastic, especially moistened with the thin, butt-kicking salsa set upon every table in squat-legged crocks. Deshebrada gorditas filled with long strands of beef need no additional moistening, as the piquant beef stains tortillas, and hands, with a brilliant red-orange oil. Other gordita fillings include tripe, tongue, chorizo (sausage), chicharron (pork skin), barbacoa (beef) and flavorless chicken that should be avoided.

Taqueria Jalisco is a Mexican restaurant, in contrast to our area's many Honduran and El Salvadoran restaurants whose menus include (but don't excel in) Mexican dishes. The business has been in Terrytown for three years, though the space, and in particular the disintegrating chair cushions, appear to have been around much longer than that. The place is worn in, the service casual and the vibe comfortable. The same two people watched what seemed to English-speaking ears like the same Spanish-language soap opera every time I visited. And there's a small adjacent store stocked with mole sauce, corn husks and chayotes that looks like someone just kicked open the door to the restaurant's storeroom.

You can't always judge a restaurant by its gorditas. Unsavory experiences with an oil-logged chile relleno and leather-tough beef fajitas taught me to ignore the other "platos (meat and fish-based entrees)." Chicken enchiladas were dry and riddled with limp chicken skin. The gratis tortilla chips bordered on stale as often as they arrived fryer-hot and crispy. And while I enjoyed the melon, pineapple and lemon juices -- all containing real fruit pulp -- so did the fruit flies.

I can, however, get behind Taqueria Jalisco's beef soup. Cabbage, carrots and zucchini fill out a deep bowl, and unidentifiable cuts of beef and bones eek flavor into the clear broth. This soup sings when seasoned additionally with salsa and when eaten with alternate bites of the accompanying corn tortillas and soft, tomato-stained rice.

Judging from the huevos rancheros -- two fried eggs perched on crisp tortillas with mild tomato sauce -- the breakfasts are also dependable. This plate included dangerously good refried pinto beans, a side dish on every entree plate (if they aren't made with lard, they sure act like it). The guacamole, when it's available, is a rough mash of ripe avocado so freshly made it's served at room temperature. The chicken flautas are respectable if not earth-moving.

Mexicans and thrill-seekers should consider the taco as a medium for less commonplace ingredients. Cactus comes piping hot between double corn tortillas with a chopped salsa of tomato, onion and cilantro. Tender cubes of beef tongue, with the richness of liver and the flavor of beef, get the same treatment, while chorizo tacos contain ground sausage that's spicy, sweet, tart and bright orange all at once. The chicharron taco is easily one of the most intense things I've ever tried to eat. Imagine warm but unfried cracklin', glistening fat, coated with an incendiary paste of red chiles and all their seeds.

Mainly I'm happy to have found the gordita, not in the least because Taqueria Jalisco's only sign, painted on a window, is obscured by the afternoon sun's glare. It sure would be simpler -- and sublime -- if there were a gordita truck in every neighborhood.