THE OCCASIONAL culinary faux pas can be fun, so long as it's intentional.

A big part of the chef's art is presentation, and making one food look like another is an ancient joke. Adding a smile to an already elegant plate is an art in itself and gives the customer an extra insight into the personality of the chef.

Most of the time, such puns are the purview of the dessert chefs or of those patient parers who transform banquet radishes and tomatoes and onions into roses and mums and such. (Yes, I've seen deep-fried onion "blooms," and no, I'm not impressed.) And some of those dishes are just referential: "Scaling" a fish in pastry is time-consuming and impressive, though it's obviously still pastry.

But I've seen a whole raw flounder so thinly and perfectly sliced and reassembled that it seemed completely untouched, yet at the touch of a chopstick, it fell into gleaming sashimi. And those mod-American "baskets" made of Parmesan cheese or the fried potato "golden nests" at Vietnamese restaurants such as Arlington's Little Viet Garden (3012 Wilson Blvd.; 703/522-9686) sometimes look awfully close to the real thing.

Counterfeit caviars are in ready supply, especially if you consider other roes, such as the tiny, dark-orange flying fish eggs called tobiko or the larger salmon roe as makeshift caviars. Every once in a while, on a mezze or tapas menu, you'll see the mysteriously named "poor man's caviar" or "Israeli caviar" or "mock caviar," which usually are eggplant dips heavy on the dark crunchy inner seeds. That's partly a visual joke, but it also goes back to the fact that true sturgeon caviar is not kosher.

But caviar, being an emblem of expense and good taste, is frequently fodder for the other sort of fun faux, the in-crowd joke that plays against that hoity-toity image. At B. Smith's in Union Station (First Street and Massachusetts Avenue NE; 202/289-6188), for example, "Mississippi caviar" is black-eyed peas, which executive chef James Oakley turns into a sort of super-hoppin' John (remember the southern New Year's delicacy?) using smoked turkey instead of ham or hocks. (No, you don't have to wait quite that long; it will be back on the menu in a couple more chilly weeks.)

Similarly, Jimmy Sneed of Richmond's the Frog and the Redneck (1423 East Cary St.; 804/648-3764) makes what he calls "redneck caviar" out of grits, which is a nod not so much to the cheapness of corn but to the justifiable regard in which real grits are held by all right-thinking persons. Sneed also prepares what he calls "redneck risotto," a really splendid dish that is also grits (so call it polenta), flavored with aged Parmesan cheese and either chicken livers or sausage or shiitake mushrooms. (And if you ever see "redneck veal" on the menu, read turkey.)

You could fake your way through an entire dinner at the Inn at Little Washington (Middle and Main streets, Washington, Va.; 540/675-3800), where one of the most popular dishes, for carnivores as well as vegetarians, is Patrick O'Connell's "portobello pretending to be a filet mignon," seared marinated portobello caps with charred onions, a tomato-shallow reduction, crisp parsnip curls and a wild rice pilaf. He also offers a crab cake "sandwich" in which the "tartar sauce" is really a shrimp mousse and the supposed bread slices are fried green tomatoes.

But the most fun faux comes at dessert, when the "rhubarb pizza" -- a disk of flaky, croissant-like dough spread with rhubarb puree and topped with "pepperoni" (slices of baby plums or strawberries), "green olives" (pistachios) and black olives (sliced prunes) is presented by the waiter with an offer of "freshly grated Parmesan" -- really white chocolate -- and a final drizzle of olive oil (Galleano). Less elaborate, but a lot closer to home, is the version at Indigo at Great Falls (774 Walker Rd.; 703/759-4650), where the apple-cinnamon "stuffed crust pizza" is really made with pecan-phyllo dough and topped with white chocolate shavings.

Not all faux foods are so up-front. Gourmet magazine recently made a good point about how a little repackaging can make potentially unappetizing foods into trendy big sellers, in this case referring to the boom in bass. You can hardly meander through Washington's menus without being overwhelmed by the bass notes. The only catch is, a lot of the names ring off-key.

"Chilean sea bass" is one of Washington's most popular fish, especially roasted. You'll find it roasted in a crust of black and white sesame seeds at 701 (701 Pennsylvania Ave NW; 202/393-0701); roasted and served with pesto-fontina whipped potatoes at the Mark (401 Seventh St. NW; 202/783-3133); sauteed with lobster, sesame rice, curried cabbage and coco-peanut sauce at BET on Jazz (730 11th St. NW; 202/393-0975); crusted in lemon pepper and served with spinach and grilled corn at Cafe Deluxe (3228 Wisconsin Ave. NW; 202/686-2233); even enthroned in a "bouillabaisse"-style broth with squid at Melrose in the Park Hyatt (24th and M streets NW; 202/955-3899).

It's everywhere, it's everywhere. So Washingtonians who don't speak fluent seafood may be surprised to discover that this most ubiquitous creature is not a bass at all, but a meaty, chewy South American native -- so chewy, in fact, that it's really called ("Are you doing to tell them?" laughed Mark chef Alison Swope) the Patagonian toothfish.

But don't panic: There are plenty of true bass around town, starting with what locals love as rockfish, which is the striped bass (or striper for short), and our personal favorite grouper, now fashionably called, in the Hawaiian fashion, hapu upu'u.

If you hang around Dupont Circle and Pesce (2016 P St. NW; 202/466-3474), you can try a couple of cousinly basses. One is the California white sea bass, which chef Jamie Stachowski compares to a lighter-flavored bluefish, served with roasted cauliflower and hen-of-the-woods mushrooms, pureed Swiss chard and truffle essence. He also sometimes serves it with a cider-tangy succotash with cipollini (an onion-like bulb) and smoky bacon. For the striped bass, he prepares a ragout of oxtails, octopus and olives with a red wine reduction. O-righty, then.

The Thai-style soup at Persimmon in Bethesda (7003 Wisconsin Ave., Bethesda; 301/654-9860) is flavored with lemongrass and coconut milk and ladled with rockfish and lobster dumplings, with a sesame-seaweed salad for relish.

At the downtown Relish (18th at M; 202/785-1177), the fish is Catalina sea bass, the restaurant's slightly punning nickname for the California sea bass that it dolls up with nicoise olives, pancetta, pearl onions and lobster demi-beurre (a lightened butter reduction).

The Jockey Club in the Westin Fairfax Hotel (the old Ritz Carlton at 21st Street and Massachusetts Avenue NW; 202/835-2100), that bastion of old-money classicism, offers a potato-crusted black sea bass with soy-lemon sauce and julienned leeks. Not surprisingly, black sea bass is a verifiable true-blue member of the clan. (On the other hand, what is sometimes called "giant sea bass" or black bass is really a Pacific fish related to jewfish.)

Re-branding is not a new phenomenon, of course. Lotte had a long reputation as a trashfish, something French fishermen tossed into bouillabaisse after selling the better seafood; and so for some years it was listed on menus either as "lobster fish," because if cooked correctly it has something of the flavor of, well, maybe frozen lobster; or monkfish, which is still pretty much what it's called.

But talk about a success story: At Catalan (1319 F St. NW; 202/628-2299), the once lowly monkfish is served with caviar and a beet-sherry sauce; while at Barcelona at Cities (2424 18th St. NW; 202/328-7194), it gets apple cider sauce and pickled eggplant. It's roasted with braised fennel, olive and anchovy cream at Lespinasse (in the St. Regis, 16th and K streets NW; 202/879-6900).

And just to get your competitive as well as culinary juices flowing, wait till next week, when Todd English's Boston-based Olives restaurant opens (complete with oven-roasted monkfish on the bone over tomato crostini and chorizo-clam stew) right across the street from Lespinasse on the southwest corner of 16th and K (202/452-1866). Watch that intersection.