Searching for authentic Mexican food that goes beyond tacos? We were, and La Jaibita, a seafood restaurant that opened almost five months ago on Centreville Road in Manassas, didn't disappoint.

Just don't do as I did: Pop a warm corn chip with a dollop of homemade salsa into your mouth as you look at the menu. Better have a glass of water handy. As my mouth begged for relief, I noticed three types of hot sauce, including Tabasco, on the table; most customers must not be as wimpy.

La Jaibita's typed menu is straightforward, divided into sections: shrimp dishes, fish dishes, cold seafood salads and stews. A plate of tacos is available ($6), as is a fajita platter of sizzling beef ($14.50).

But fish and shrimp take center stage at dinner. All shrimp dishes are $12; all fish dishes, $9. They range from mild to spicy hot.

Read the fine print: "red and hot" means spicy, maybe too spicy unless you enjoy such food. Manager-owner Fabian Martinez steered us away from the hotter, but perhaps more authentic, Mexican stews.

On Sunday, the restaurant serves menudo, beef stew served in a homemade tortilla-shell bowl--a bargain at $5.

The tomato sauce that bathed our shrimp was fresh, thick and pleasing. The Spanish rice could have used a bit more seasoning, but the three steamed vegetables--thinly sliced carrots, a broccoli floret and slices of zucchini--were perfect low-cal sides. The handful of crinkle-cut, packaged fries that were served with the shrimp seemed unnecessary with an otherwise healthful entree.

A basket of Saltines arrived; some people eat their shrimp and sauce on a cracker, which is not a bad combination.

A companion enjoyed an avocado-topped cold seafood salad (ceviche) of shrimp, octopus and squid marinated in lemon juice then tossed with diced peppers and drizzled with lime. The seafood was piled on three tostado shells; the idea was to roll up a tostado and eat without a fork, but the abundant amount made that difficult.

Tacos are on the menu, but nothing resembling the ground-beef-mush filler common at some restaurants. For $6, we were served a plateful of five piping hot shredded chuck tacos on small corn tortillas, surrounded by freshly chopped onions and red and green peppers. A bowl of spicy ocher-colored sauce to ladle on the beef was offered.

There's a small menu section of seafood "cocktails." One--a combination of all the types of seafood available that day--is named "Come Back to Life," the name by which it's known in Mexico, Martinez explained.

Martinez has been in the restaurant business 15 years. He owned a place in Monterrey, Mexico, before moving to the United States six years ago.

Most of the seafood comes from North Carolina. Although the restaurant name means "the little crab," crab is not on the regular menu.

The lunch menu is limited--no shrimp--but includes tacos and a $4.99 special that includes a fish filet, fries, rice and a salad.

Spicy food cries out for cold drinks, and the beverage list is extensive, ranging from pink lemonade to daiquiris and several Mexican beers.

It's a happy, low-key place; don't be surprised to hear the chefs singing in the kitchen as they prepare for the dinner crowd.

Got a Prince William restaurant you'd like to spread the word about? Send e-mail to shumansk@washpost.com or kovachs@erols.com, or mail to: 9524 Center St., Manassas, Va. 20110

LA JAIBITA

* Address: La Jaibita, 8059 Centreville Rd., Manassas, 703-330-0577

* Hours: 10 a.m.-11 p.m. Monday to Friday; 10 a.m.-midnight Saturday and Sunday.

* Credit cards: Accepts all except Discover. Does not accept personal checks.

* Prices: $4.99-$14.50 for meals; sides about $2 each.Our bill for three meals came to $48.32 with tip.

* Children's menu: Coming soon; meanwhile, ask the server.

* Low-fat selections: Fish and some seafood dishes.

* Health-conscious: Yes, but some foods are very spicy and hot.

* Atmosphere: Casual.

* Downside: In a small shopping center, it could easily be overlooked. Look for the yellow neon sign in front. Front parking lot is small; more parking is available in back.

CAPTION: Fabian Martinez, owner of La Jaibita, also owned two restaurants in Mexico.