Jefferson (in the Jefferson Hotel)

1200 16th St. NW (at M Street). 202-833-6206

Open: for breakfast daily 6:30 to 10:30 a.m.; for lunch Monday through Saturday 11:30 a.m. to 2:30 p.m.; for brunch Sunday 11 a.m. to 2 p.m; for tea daily 3 to 5 p.m.; for dinner daily 6 to 10:30 p.m. All major credit cards. Smoking in bar area only. Metro: Farragut North. Valet parking. Prices: lunch appetizers $9 to $15, entrees $12 to $23; dinner appetizers $9 to $18, entrees $25 to $37. Full dinner with wine, tax and tip $65 to $100 per person.

Signatures

801 Pennsylvania Ave. NW (near Ninth Street). 202-628-5900

Open: for lunch Monday through Friday 11:30 a.m. to 3 p.m.; for dinner Sunday through Thursday 5:30 to 10 p.m., Friday and Saturday 5:30 to 10:30 p.m.; bar menu Monday through Friday 11:30 a.m. to midnight, Saturday 5:30 p.m. to midnight, Sunday 5:30 to 10 p.m. All major credit cards. Smoking in bar area only. Metro: Archives-Navy Memorial. Valet parking after 5 p.m. Prices: lunch appetizers $7 to $10, entrees $12 to $22; dinner appetizers $8 to $15, entrees $21 to $36. Full dinner with wine, tax and tip $70 to $100 per person.

Anyone who believes there are no second acts in life hasn't eaten out much. Few are the restaurants that remain the same, year in and year out; indeed, the business is famous for talent that comes and goes on a whim, and menus and service that fluctuate like the stock market. Charting those ups and downs keeps restaurant critics employed -- and recently sent this one back to two upscale Washington restaurants that show signs of renewed vigor.

For too long, the Jefferson, in the downtown hotel of the same name, was like a pretty face concealing a dull wit. The clubby dining room was easy on the eyes, with its leather-colored walls, but saddled with generic service and food to match. The cooking took some welcome steps forward last fall when the owner, Loews Hotels, tapped Jeff Tunks, the chef and co-owner of the popular DC Coast, to work his magic on what had become a very tired menu. Recently, Tunks and the hotel decided to end their relationship, and Jason Lage, who cooked at the late Saint Basil in Reston, took over day-to-day cooking duties.

One taste of the fried oysters underscores the Jefferson's new thinking -- and signals that fish and seafood generally are the way to go on the menu. Sheathed in a light cornmeal batter, the oysters crackle at a bite; a loose hash of corn and mushrooms and an assertive remoulade add jazzy notes. Another appetizer, a big, creamy crab cake, is, like a lot of the food, architectural in design, rising from its luscious base of diced sweet potatoes and rich bacon. Smoked salmon layered with bagel crisps, however, comes across as something the kids would whip up for a surprise breakfast in bed for Mom and Dad.

Among the entrees, Dover sole arrives at the table decked out with fried parsley and velvety mushrooms. Salmon simply melts on the tongue, and an assertive sun-dried tomato vinaigrette keeps it and its soft polenta from getting boring. Rack of lamb races to the front of the meat pack, with its little tower of goat cheese and ratatouille and a bold sauce of olives and red wine. The eggplant fries that accompany it quickly go soggy, though. And the wine list -- well, why is it so difficult to find a wine that doesn't require taking out a bank loan?

The desserts, delivered from DC Coast, run to a soothing sort of apple cake with lashings of caramel sauce, and a tangy lemon tart, elegant with its glassy bruleed surface. They're last impressions worthy of their handsome setting.

"I'm halfway through the menu and I don't see anything I recognize yet," I overhear an out-of-town business type joke to his equally baffled table mates as he reads aloud from the dinner menu at Signatures. "What's Nigerian paprika coating? . . . And Forbidden Radicchio Risotto?" The waiters here earn their pay, going into epic explanations of what the restaurant's new chef, the Ivory Coast-born Morou Ouattara, is cooking now that he's left Red Sage and taken over the kitchen of this civilized, year-old restaurant overlooking the Navy Memorial. One thing is certain: The menu is not a predictable rehash of contemporary American restaurant cooking.

No other list around packs so many ingredients -- or so many food fashions -- into a single page of appetizers and entrees; the caramelized Maine lobster alone manages to include "truffled tapioca," a fennel confit and olive oil foam. But behind some of the many adjectives and techniques, there's plenty to hold a diner's attention -- far more than when the restaurant opened last spring. If you order only one starter, make it Ouattara's fetching Deconstructed Quail. The breasts are fried to a gentle golden crisp, threaded on small skewers and arranged with a lemon-brightened quinoa salad and two figs, fat with foie gras pate, on a fig-port reduction. It's a fascinating weave of flavors and textures. Unfortunately, that success doesn't carry over to Lobster and Pearls, where morsels of seafood drowning in coconut milk are mismatched with seaweed and a topping of tapioca beads stained black with squid ink. It's like a seviche with no spark.

The meat dishes are particularly appealing. Ordering the playfully named Head to Tail yields a seriously delicious three-part examination of domestic Kobe beef. A white rectangular plate serves as a canvas for beef cheeks paired with crisp-soft okra and silken diced foie gras; tender grilled short ribs flavored with wine, lemon zest and chili flakes; and Kobe tail bound in crisp shells of cracked wheat. It is just a few bites of each, and a reminder that the chef knows how to use all the parts of the animal. On the homey end, there's a very good pork chop from Niman Ranch, brined and smoked. Some braised collards and sweet potato puree give the flavorful meat a nice Southern accent.

Seafood dishes are iffier. Cylinders of seared tuna are dusted in harsh curry seasoning but salvaged by some intriguing accompaniments, including a brassy lemon-grass sauce, pickled carrots and onions, and pleasantly sticky black rice flavored with Parmesan cheese. (This is the mysterious Forbidden Radicchio Risotto.)

Desserts also pose a problem. The chocolate dome, with its fluffy ganache center, resembles a Three Musketeers candy bar -- it's achingly sweet -- while both parts of the creme brulee, a duo in mocha and vanilla, sport bulletproof burnt-sugar toppings and custard centers that taste like butter. Fruit sorbets are heavy rather than delicate. Give me instead the simple fruit crisp, bursting with sour cherries beneath its crunchy oat cover.

As for the dining room, it continues to be a handsome blue-and-gold backdrop to the myriad autographed photographs and documents for which Signatures is named. The service remains on course, too: It's a pleasure to see the same polish, only now with more confident cooking.

Ask Tom

It's happened twice now to Irwin Kaufman, a Washington reader: Restaurants that promise to be open till a certain time actually close earlier -- even when he has specifically called in advance to confirm the hours. "Don't restaurants have an obligation to be open when they say they will?" asks Kaufman, who likes to eat late after he's been to the theater. Of course they do. Barring extreme circumstances -- say, exploding manhole covers that force street closings -- restaurants should keep the hours they publicize. Better for a business to trim its schedule than to overpromise and underdeliver.

Got a dining question? Send your thoughts, wishes and, yes, even gripes to asktom@washpost.com or to Ask Tom, The Washington Post Magazine, 1150 15th St. NW, Washington, D.C. 20071.

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