RESTAURANTS : NO MORE KIDDING : Young, Talented Chef Jean Pierre Bosc Won Fame at Fennel; Is He Losing It at Castel Bistro?

We expect great things of Kid Bosc. Jean Pierre Bosc, who is only 30, had impressive credits when he came to town four years ago. He’d worked with such French restaurant greats as Paul Bocuse, Yann Jacquot and Michel Rostang. At Fennel, where Bosc was the year-round resident chef, Jacquot and Rostang alternated months alongside him in the kitchen.

Eventually the Kid left, Fennel closed down (it recently reopened in a new location), and Bosc bounced around to Le Comptoire in New York and briefly to La Serre in the San Fernando Valley. Now he’s both executive chef and a partner at Castel Bistro, a place that bucks the Italian trend by specializing in the cuisine of Provence. This sounds hot.

Well, sometimes it is; sometimes it’s warmish. The problem isn’t that the food is bad (though I have a problem with the lamb osso buco ) or even middling. It’s that you feel the Kid was meant for better things than this.

Maybe I’m being harsh. After all, Fennel was always a high-ticket joint, while Castel has a post-recession menu that reverses, at least to some degree, the price creep that continued for months even while certain L.A. restaurateurs ought to have been paying attention to the economic news. Most entrees here are on the cautious side of $15, and that may place certain limits on a chef’s imagination.

Maybe the room is part of the problem. It has high ceilings, but somehow it doesn’t seem spacious, maybe because of the odd-shaped bite the bar takes out of the floor plan. The management has promised to replace the garish paintings (“colorful,” as one waiter described them), and that may help things. But I don’t know. An awkward, shabby quality hovers over Castel.

Some of the best things on the menu are round. The smoked salmon salad, for instance--a flat mass of warm lentils mixed with vinegar and shallots, enclosed in thin-sliced salmon--or the smoked salmon tart, which is a similar shape but has an onion-and-goat-cheese filling. (Play your cards right and, at the end of the meal, you can have another pincushion-shaped thing, a crepe enclosing coffee mousse.)

The mussels poulette rate pretty high, too, not so much for the shellfish, which are outstandingly tender but rather bland, as for the cider-and-cream sauce sprinkled with chives--it could stand on its own as a soup. In fact, I’d rather have it than the bland cream of butternut squash soup. And I’d rather have the salmon rillette terrine, despite its silly name (it’s just layers of fresh- and smoked-salmon puree surrounded by dill-sprinkled cucumber salad) or the goat-cheese terrine wrapped in eggplant slices than the escargot of pink scallop. Bosc may call this an “escargot” because the dish is flavored with garlic, butter and herbs or because the scallops are almost as chewy as your average neighborhood-restaurant snail.

The short pasta list includes ravioli dyed black with squid ink, served with a sweet, aromatic and startlingly yellow-orange sauce of pumpkin and saffron, and stromboli , which, for those who have not learned this restaurant convention, are not pasta but in effect sandwiches made from hollowed-out Italian bread. You’ve got your spinach stromboli , and you’ve got your lamb-and-ratatouille stromboli.

Castel specializes in seafood, but you can get some good meat dishes, such as the butcher’s cut, also known as hanger steak, a somewhat chewy but extremely beefy cut called onglet in French. Bosc will either saute it with red wine or--the way to go--grill it with sea salt, pepper and olive oil. Sometimes Bosc makes a good lamb stew with carrots, broccoflower, potatoes and a strongly herbal gravy. However, even a taste for well-done meat may not get you through the osso buco of lamb--a lamb shank served on white beans, cooked so dry it crunches greasily between your teeth.

Only one of the seafood dishes does anything for me: the sauteed whitefish, which comes under a tumbleweed of fried leek threads and over a red-wine-and-leek sauce with a faintly medieval dash of cinnamon.

The rest all seem to go astray. The bed of lentils is the best part of the grilled mahi-mahi, meaty and smoky, as if cooked with a smoked ham hock; the fillets themselves tend to be unintentionally blackened. The rich Chilean sea bass served on mashed potatoes is a shade overdone and mushy, and the tomato broth in the bouillabaisse salty and one-dimensional, as if made with commercial broth.

What could surprise us now? Well, dessert could. Yes, they call this place a bistro, but the dessert list will probably give an old Fennelite a turn. It’s a staggeringly retro collection from the early ‘70s or before. Some of these are still popular, such as tarte tatin (the apples baked on a sort of crisp biscuit--more round food) and creme caramel, a rather thick and eggy version of the latter.

But it may have been a while since you saw chocolate marquise on a menu--a thin slice of velvety, inoffensive chocolate pastry accompanied by pistachio ice cream that must be homemade because you sometimes find pieces of shell in it. The dessert of choice is a version of that ancient favorite, belle Helene: a poached pear with vanilla ice cream and hot chocolate sauce.

Strange. If another chef were behind all this, you’d think: OK, a sort of bistro. But with Kid Bosc in the kitchen, the mind reels. What’s going on, Kid?

Castel Bistro, 12100 Wilshire Blvd., Los Angeles; (310) 207-4273. Open Monday through Saturday for dinner, Monday through Friday for lunch. Full bar. All major credit cards. Parking lot on Amherst Street; validated at lunch, valet parking from 6 p.m. Dinner for two, food only, $40-$67.

THE WINE LIST

When you pay a premium over retail for wine in a restaurant, you expect a clean wineglass and assistance from the staff. Castel failed me on both counts. Our glasses were dirty, spotted and stained with lipstick. The glasses on the table next to ours were dirty, too, as were all those I spotted (as it were) in the place.

Then came the “service.” I asked for the wine list and got it. Within seconds the waiter came over and asked if he could help with the choice. No problem, I said, except that we hadn’t seen menus, so I had no idea whether, for starters, we wanted red or white.

After that, things improved. The offending glasses were whisked away after we ordered a bottle of red wine. The waiter brought spotless stemware for the 1988 Phelps Merlot, $24.

The wine list here is short, just 31 selections, but it includes some nice wines in a wide range of styles: a crisp 1990 Muscadet, $22; a rich 1989 Mondavi Chardonnay, $26; a light red 1990 Drouhin Beaujolais Villages, $17; an aged 1988 Phelps Cabernet Sauvignon, $32, and 12 wines by the glass.

Food stylist: Alice M. Hart/ Food for Film