WEST END CAFE -- One Washington Circle NW. 293-5390. Open: for breakfast 7 to 10:30 a.m. daily; for lunch 11:30 a.m. to 2:30 p.m. Monday through Saturday; for brunch 11:30 a.m. to 2:30 p.m. Sunday; for dinner 6 to 11 p.m. Sunday through Thursday, 6 to 11:30 p.m. Friday and Saturday. Reservations suggested. All major credit cards. Separate non-smoking section. Valet parking at dinner. Prices: lunch appetizers $3.95 to $5.75, entrees $6.50 to $16.95; dinner appetizers $3.95 to $6.75, entrees $7 to $18.25. Full dinner with wine, tax and tip about $25 to $40 per person.

Restaurants are about as reliable as the stock market. You follow a hot tip, and the chef is out sick. Or you warn your friends about a place, and they find the meal of their lives. It happens to you, it happens to me, and it happens to restaurants themselves.

I heard that Herb Kaplan, who had once run the West End Cafe and then opened G. Pinchot, was back at the West End after its chef, Janet Terry, left to open Samplings. (Herb Kaplan turned G. Pinchot over to Herb White, who brought the name from Herb's on P Street. But that's the restaurant business: confusing.)

So one day I returned to see West End's latest stage, and I found it at least as good as ever. Another day I found it mixed -- a good dish, a bad dish, a neutral dish. But both times the service was exceptional. On a third visit there was another twist: good food, bad service.

At lunch, service has been spiffy, professional and well informed. But when I arrived for dinner one evening, no host was there to greet the waiting diners. The entrance started to fill, and the guests grew restless, while a waiter sat talking to some customers. After a while, a hostess showed up and started seating the accumulated crowd.

From then on the dining room ran smoothly. Was the initial havoc an aberration? Were my beautifully served lunches the true measure of this restaurant? It's a gamble.

The cafe' has two rooms, one lively with a piano bar, the other quiet and comfortable with lush plants under a greenhouse roof. Even without tablecloths, these dining rooms are festive.

The menu is American, modern, short and interesting, including a section of "Light Fare" from which a meal could be put together for less than $10. Appetizers are a string of appetizing inventions. Grilled tequila shrimp taste fresh (and sometimes a little tough, as fresh shrimp can sometimes be), blending grill smoke and tequila to play against chili-hot tomatillo salsa. They are outstanding shrimp. I'm also fond of the smoked salmon and dill waffle -- which is exactly as it sounds and a delicious combination, garnished with American caviar and cre`me fraiche. But it is so large it needs to be shared or followed by something light. Grilled lamb sausage has sizzling spiciness and, except for the watery mustard sauce, it was a savory start. Chive ravioli were doughy wrappers with a gummy eggplant filling, but the caper-spiked tomato "coulis," actually a chunky Mediterranean-tasting tomato hash, is good enough to top anything well. As for soups, don't pass up black bean if it is the day's special.

That should lead you to consider black bean chili on the light fare list. The sleeper there, though, is eggs benedict, a perfect classic with eggs just runny and the hollandaise light and lemony. The Mediterranean salad, with crisp greens and potent olives, fell short only because its London broil garnish had dried out and lost its crustiness. If you are looking for a main-dish salad, the beef and broccoli on fat Japanese soba noodles is an artistic arrangement with the crunch and tang to match its colorfulness.

Among the more substantial main dishes, the thick, pale veal chop is a stunner, browned but left faintly pink, its topping of pancetta, leeks and wild mushrooms a pungent foil for the veal. Lamb fared less well. Ordered medium rare, it came with no pinkness, and the dryness was not relieved by the scant sauce. The sauce was also lost on the sweetbreads, and they were spongy rather than creamy smooth. As for fish, one day's blackened redfish was just spicy, overcooked fish. Another day's fresh tuna stuffed with cheese and sage sounded like a mistake in the making but was extraordinarily good.

West End Cafe arranges its plates artfully, and its vegetables could star on their own. Saute'ed spinach with bits of corn or crisp green beans are typical, along with new potatoes tossed with rosemary.

The desserts sound irresistible -- and a few of them are. Orange macadamia crepes were a comedy of errors one night when somebody mistook mayonnaise sauce for cre`me anglaise, but when made correctly they are beautiful cornucopias of fresh fruit in nutty (though too-thick) crepes. And a few months back, West End Cafe was serving the only authentic and delicious summer pudding I have had in Washington. But bourbon pecan pie had a tough, thick crust, and its filling was sheer sugar excess. Cre`me brule'e was unappealing dumped in a sherbet glass, its sugar topping barely browned and the custard thick and gummy.

This is a kitchen that makes some mistakes, even silly mistakes. But it is a kitchen with imagination and flair, one that can produce really delightful cooking. For a moderately priced restaurant, West End Cafe offers a great deal of style. ::