by Charlotte Bruce Harvey

On a blustery fall night with rain pouring down on Harvard Square in thick sheets, entering the amber glow and pitched chatter of Chez Henri was a joy. It seemed just as a bistro should be: loud, casual, warm, and nourishing. Opened October 4 by chef-proprietor Paul O'Connell, of Brookline's celebrated Providence, Chez Henri occupies the storefront near the corner of Mass Ave and Shepard Street, where for nearly half a century Chez Jean was a Cambridge landmark. Hanging above the sidewalk, Chez Henri's brand-new red metal sign exudes that same air of permanence; it feels classic, but with style - a premonition of things to come.

For the menu, O'Connell and chef de cuisine Corinna Mozo have taken a handful of bistro basics and given them a little something extra - "a Cuban twist" the ads say - which lifts Chez Henri above the hidebound tradition that might constrain a more genetically pure French establishment. The spinach salad ($6.95), would have been ordinary, if wonderful - it came tossed with bacon and a pungent grainy-mustard vinaigrette - were it not topped with warm homemade tamales stuffed with duck and mild chilies. They were irresistible, every bit as soft and inviting as the ,mustard dressing was tart and percussive.

A bowl of mussels ($5.95) was all tradition, bringing back memories of a tiny Parisian bistro. The steamed shellfish were fresh and plump, served in a creamy saffron broth. To soak up the broth were croûtes, grilled and saturated with garlic butter. When those were gone, good French bread filled in admirably. A bowl for the empty shells, however, would have made it easier to keep slurping indefinitely.

O'Connell has brought frogs' legs back from wherever they disappeared to over the past 20 years: they came breaded and fried crisp, in a rich brown sauce loaded with garlic, lemon, and thyme ($7.95), another excellent excuse for mopping up sauce with bread. Escargots ($7.95) seemed too restrained, however. A half-dozen fat snails were doused in a garlic, butter, parsley, and cognac sauce, then stuffed back into decorative shells; although the snails were well-cooked, there wasn't much sauce and the plate seemed lackluster. More successful was smoked salmon with frisée ($8.95). A tangle of chicory in a tart lemon vinaigrette accompanied several generous slices of outstanding smoked salmon, a soft-poached egg, and brioche. It was like breakfast at dinner, at once tender and tangy, bracing and coddling.

Among the entrees, the blanquette de veau ($13.95), a rich but delicately flavored veal stew, is the ideal winter comfort food. It's considered a dish for convalescents in France, and with good reason: it makes you feel good. O'Connell juxtaposed sweet pearl onions and earthy shiitake mushrooms to bolster the stew, and he served it on a bed of thick, fresh pappardelle-style egg noodles. It's one of the most popular dishes on the menu. Another is the steak frite ($18.95): a pan-fried strip steak that came with an enormous haystack of crunchy, golden french fries. The bordelaise sauce on the steak was made with a sofrito base - lard with annatto and peppers - which gave it a smoky, sultry Caribbean flavor and took the steak out of the realm of the ordinary.

Paella "Cuban style" ($16.95) was a rich melange of saffron rice, chicken, homemade chorizo sausage, and shellfish, and filled the air with garlic. The shrimp, however, were a little tough, as though overcooked, and the overall effect of the dish was oily. A small fillet of monkfish ($17.95) was roasted until mahogany brown on the outside and tender inside, then served in a pool of cream sauce flavored with calvados (apple brandy), with a huge portion of fried onion rings that were as lightly battered as the finest tempura.

Trout à la Meunière ($17.95), a butterflied filet of trout, was sweet and earthy, served in a brown-butter sauce with tender shrimps and capers. With it came new potatoes and long, thin haricots verts sautéed in butter. Since most of Chez Henri's entrees come without vegetables, side orders are a good idea - and at $3.95, big enough to share. The sautéed spinach was silky and loaded with garlic; tostones (smashed and fried plantains) were crisp and sweetly starchy.

Among the desserts ($5.50), the lemon tartlette is well worth saving room for - an individual-sized tart au citron in a buttery hazelnut crust. It came in a pool of sharply minty crème anglaise with a few raspberries, blackberries, and slices of starfruit. The baked feuillette de pommes was another tiny tart, filled with paper-thin apple slices, baked and topped with appealingly bitter burnt-caramel ice cream. The gâteau au chocolat was simple, a slice of warm, rustic-looking dark-chocolate cake, served with vanilla-flavored whipped cream.

Chez Henri's Cuban influence came through in the sweet leche fondue: sugar, cream, and milk thickened to the consistency of honey, then dusted with cinnamon and served as a dipping sauce with slices of kiwi, starfruit, strawberries, and orange. Bliss.

Chez Henri serves good, strong dark-roast coffee and excellent espresso and cappuccino, as well as a fine cup of tea. The wine list features several whites and reds between $15 and $30 a bottle, as well as some finer vintages. A welcome convenience is a wine special - one red, one white - sold by the glass, half carafe, or bottle.

In addition to the menu à la carte, Chez Henri offers a prix fixe three-course dinner for $28, which changes every three days. Service is friendly and unaffected, although halting at times, a forgivable problem in a start-up. Even though it opened only recently, Chez Henri is already drawing crowds, and reservations are wise. After 10 p.m., when the kitchen stops preparing the dinner menu, you can order off the shorter but no-less-tempting bar menu; its Cuban sandwiches and braised oxtails have already become famous, a great not-so-light meal after a play or a movie in Harvard Square. It's one of the few genuinely smoky bars left in town. Cigars, anyone?