THE COLLECTOR -- 1630 U St. NW. 745-1825. Open: Monday through Thursday 6 p.m. to midnight, Friday and Saturday 6 p.m. to 1 a.m., Sunday 6 to 11 p.m.; for brunch Saturday and Sunday 11 a.m. to 3 p.m. All major credit cards. Reservations suggested for parties of four or more. Separate non-smoking section. Prices: dinner appetizers $2.75 to $4.25, entrees $4.95 to $12.95; all-you-can-eat buffet brunch, $8.50. Full dinner with beer, tax and tip about $20 to $25 per person.

Tired of caviar? Overdosed on holiday pheasant and truffles? At the Collector you are welcomed back to basics, for this is a meat loaf and mashed potatoes restaurant.

It is one in the struggling strip of restaurants on U Street NW, sharing the block with Julio's and Stetson's since Torremolinos finally gave up the fight. And after many months of changing chefs and menus, opening for lunch, then closing for lunch, the Collector has settled into a stable menu and steady hours -- now limited to dinner and Saturday and Sunday brunch.

The Collector is as much an art gallery as a restaurant. The collection of art on display and for sale changes every few weeks, so the mood of the place varies as the artwork swings from African masks and marriage cloths to turn-of-the- century travel posters and modern abstractions. Through these changes, though, the Collector remains a breezy- looking cafe' with black-and-white checkerboard floors and laminated tables inset with pages from antiques catalogues. Its indoor trees and walls of windows combine to create the open feel of a sidewalk cafe'. Whether you're having a drink at the long, carved-wood bar or a meal in the adjacent dining room, the Collector is a welcoming, attractive place to linger.

And linger you will, for the kitchen is so slow you might wonder whether the early Americana on the menu means the kitchen has forsworn all time-saving devices. I've waited for an appetizer that never came, asked for it with my main course and canceled it when that course was finished. I shudder to think of the delays when the dining room is full. On my last visit, two of the appetizers and two of the main dishes were unavailable, which narrowed the choices considerably. Service is friendly and cheerful but not very attentive. The waiter is likely to need reminding if you want water, he may not listen to all the details and may forget who ordered what. The Collector, even after being open all these months, needs to get organized.

The restaurant's ideas outstrip the execution. The menu is inviting, with four kinds of fritters and old-fashioned corn chowder to start. The chicken salad and draft beer are named after Ma Wooby -- the owner's grandmother, we were told. Main dishes continue the homey American theme: barbecued chicken, chicken-fried steak, chicken pot pie, pulled barbecued pork, meat loaf and pan-fried catfish plus the inevitable burgers. In addition to a small, reasonably priced wine list, there is a list of beers including Bulmer Woodpecker Cider, two Watney's brews and Chesapeake Bay beer on tap.

Even more endearing are the accompaniments. The basket of bread alone is worth a visit. Big, doughy, crusty drop biscuits are clearly made in-house, as are compact, sweet corn muffins and pumpkin raisin muffins. In fact, the single best dish at the Collector is a side dish. It is Texas mashed potatoes, wonderful lumpy, buttery mashed potatoes with bits of skin, their crater filled with medium-brown authentic-tasting gravy. How delightful it is to sit in an art gallery and eat biscuits with great mashed potatoes and gravy, washed down by a dark, full-flavored microbrewed beer.

To balance out the meal, though, you might want to order meat loaf. It goes ideally with the biscuits and mashed potatoes, for it is plain old diner meat loaf, soft and gravy-soaked.

Nearly everything else is risky. An appetizer of crab puffs is fine, the shredded crab meat formed into crunchy fritters and served with a too-sweet mustard dip (accompanying dips are a continual problem here). Cheese fritters are also crisp-crusted and agreeable, with an interesting jalapenåo-spiked apple butter for dipping, but the restaurant's measly portion of four tiny fritters is disappointing. Apple corn fritters could have better passed as hush puppies, for their cornmeal batter was heavy and we found bits of corn but no apple in them. The menu also features corn chowder, but one day it was a spicy and delicious potato chowder with corn, while another day the potatoes and corn were there but the flavor was missing. It was just a thick, starchy, oversalted sludge.

As for the entrees, you can probably count on the pan-fried catfish, for it is fresh and moist, with a light, crunchy coating. The fish is filleted rather than fried whole, and though purists might object, it is skillfully prepared. Grilled pork tenderloin starts out fine, rubbed with seasonings, grilled, sliced and fanned out. But the accompanying cold mustard sauce is so sweet that it overwhelms the meat, and the cold is more startling than complementary. Chicken pot pie and pulled barbecued pork have little to redeem them. The pot pie is more like soup -- with bits of what taste like frozen peas and carrots floating with nubbins of chicken in an opaque sea -- and the puff pastry crust is wet and greasy. The barbecue is almost as wet, the soggy shreds of meat limp in a sweet, watery red sauce.

And then there's blackened fish. Clearly, a kitchen with such a basic level of skill should not attempt blackened fish, but one night it did. It missed the point. Not only was the blackened fish a butterflied trout -- which is too thin to subject to such high-fire cooking -- but it was cooked so long that it was chewy throughout. The coating of blackened spices was delicious, but the fish itself was irrelevant.

As a cold entree you could order Ma Wooby's chicken salad, but it is merely chicken drowned in mayonnaise and with no apparent seasoning -- hardly worth naming after somebody.

In addition to the world-class mashed potatoes, side dishes include a choice of vegetables such as "stir-fry," which turned out to be barely cooked green beans with zucchini slices, and scalloped apples, ultrasweet and heavily spiced. Actually, the scalloped apples would be a good dessert. And if apple brown betty is available as a dessert, remember this is a kitchen that deals well with apples, from the jalapenåo apple butter to the scalloped apples to this nutty homespun dessert. It is topped by very good ice cream, or you can order the ice cream as a sundae.

To put all this in perspective, look on the Collector as an art gallery with better food than most galleries and a diner with better art on the walls than most diners. ::