Pan Thai is a modest, competent restaurant at the scene of some dining history. This space was once the original Thai Cuisine — Boston’s second Thai restaurant. More recently it was Cena, a much-lamented near-vegan gourmet restaurant that revived the question, " Why can’t Boston support a nationally known vegetarian kitchen, like Greens in San Francisco? " As Pan Thai, the place now offers an excellent answer to the question, " Where should we eat before the symphony or Huntington Theatre? "

Cena’s sponged orange walls are now a tone poem in shades of green, with tastefully selected Thai objets d’art and paintings here and there. From outside, the restaurant appears to be a tiny storefront, but the main dining room extends far back and up four steps.

Among the many appetizers, we found all our fried selections impeccable, especially the crispy tofu ($4.25), which was very fresh and crisp triangles with a nice sweet-chili sauce. Steamed dumplings ($5.95) are a little doughy but have a flavorful shrimp-pork filling and a novel touch: a topping of caramelized onions. Fresh rolls ($3.95), which I associate more with Vietnamese cooking, are overlarge here, and the wrappers are somewhat rubbery. The bounce lies in the filling of noodles, lettuce, mint, and cucumber, which is still a fun way to eat salad.

Larb gai amnat ($6.95) is cubes of your choice of chicken or beef, in a rather spicy sauce with fresh cilantro and leaves of iceberg. The leaves can be any kind of lettuce, but have to be large enough for wrapping, which really makes this kind of appetizer happen. Edamame ($3.75) are fresh green soybeans, which are more usually found in Japanese restaurants, but fresh soybeans are so cute and tasty that I’m sure they eat them this way anywhere they grow. ( " This way " is in the fuzzy shells, sprinkled with salt. You push them out between the teeth, thus getting the salt as well as the jewel-like beans inside, which taste like less-starchy limas.)

For the size of the restaurant there are also a lot of entrées, especially in the noodle category, where Pan Thai features some preparations not often marketed to Bostonians. Crispy pad Thai ($8.95) is actually the fried thin noodles used to make mee krob, with most of the typical flavorings and toppings of pad Thai: shrimp, noodles, chicken, bean sprouts, chopped peanuts, and a sauce that is sweet, salty, and sour.

Grilled-chicken lemongrass ($10.95) is a fusion dish. You take a most un-Asian slab of boned chicken breast, but marinated in some spice and a lot of the citronella aroma of lemongrass, and char it slightly on the grill. The vegetables are a Jae’s-like mess of green beans, zucchini, carrots, onions, broccoli, baby corn cobs, and various mushrooms, all in a light, slightly sweet, soy-based sauce. Seafood typhoon ($12.95) — the very name connotes fusion — is an excellent medley of four mussels in the shell, with shrimp, squid, and a few scallops, in much the same light soy sauce, but powered up with leaves of Asian basil and hot pepper.

Grilled jumbo shrimp ($12.95) is a very good grilling job, leaving the shrimp still soft and toothsome, and a choo chee sauce (spicy red curry plus a lot of galangal and lemongrass) over a similar vegetable medley, but with more bell peppers. If you’re on a high-protein diet, you may prefer garlic shrimp ($11.95), which has a lot of ginger flavor along with the garlic, but is mostly a stir-fry of shrimp, cooked lettuce, and onions.

My only un-favorite at Pan Thai was beef with pineapple ($8.95), not so much for the sweet sauce, but for the use of pink tomato and baby ears of corn. These are two particularly weak vegetables in a dish dominated by the fruit more than the beef.

Rice ($1 per person) is real Thai jasmine rice, nicely made. The list of wines and beers is about what you might expect — inexpensive wines that don’t really stand up to the food, and bottled beers that do, including Singha, a malty Thai beer. The restaurant also offers a list of Asian-style drinks, and some sodas. I tried a lime rickey ($1.75), which tasted only a little sharper than 7UP, despite visible wedges of lime in the drink.

Pan Thai has several desserts, as is increasingly the fashion at Thai restaurants. The one that will really please concertgoers is cheesecake ($4.75). It isn’t that you need a bit of richness after Asian food, but that this is served as five micro-cheesecakes, each no more than a bit of cheesecake, crust, and a little jam. So you get the idea and the moment of a heavy dessert, without all the calories. Taro pearls ($3.75) is a hot, sweet coconut soup with bits of purple taro and some purple-clack sticky rice. Kao neil mamueng ($4.75) is a dish of half a mango alongside some sticky rice cooked up sweet and rich with coconut milk. I’ve eaten riper mangos, but the more acidic fruit does cut the sticky rice somewhat, and this is probably the point of the pairing in a place where mangos grow on trees, but sticky rice has to be soaked all night before cooking.

Service at Pan Thai was excellent during our before-theater rush. There are perhaps five Thai restaurants in a radius of as many blocks, but this is clearly the closest, the cheapest, and not far from the best.

Robert Nadeau can be reached at RobtNadeau@aol.com