There was a time in the not-so-distant past when Castro Street was known as a hub for Asian restaurants (and, frankly, little else). But things have changed. Today Mountain View boasts a diverse selection of restaurants, retail stores and night life that have transformed the downtown into a more vibrant destination.

Yet the Asian restaurants are still quietly doing business, and continue to represent the predominant dining choice on Castro. Kirin Chinese Restaurant is such a place, and its owners, Ben and Dennis Yu (who are otherwise unrelated), are members of the old guard. They bought Kirin in 1989 while it was in its 22nd year, and the establishment has remained virtually unchanged in the interim.

A line of fish tanks teeming with live seafood greets you upon entry. Yet another wall of tanks is stocked with live lobsters, which struggle against the tongs that occasionally appear to pluck them out. The entire place is encircled with brightly colored wallpaper borders depicting dragons, firebirds and orchids. And fantastic, ornately carved screens set apart a second, smaller dining room and a semi-private alcove with a table for 12.

Hanging next to the kitchen door are pink laser-printed signs offering the day's specials in Chinese — without an English translation. This place oozes authenticity.

For starters we tried won ton soup ($6) and an order of spring egg rolls ($6). The soup was a generously sized bowl of clear chicken broth brimming with meaty won tons, plump and perfectly de-veined shrimp, barbecued pork (rendered pink around the edges by a sweet marinade), mushrooms, big flowers of bok choy, and carrot juliennes. The chef used a judicious amount of spice, allowing the ingredients to work individually and in tandem, depending on whichever combination wound up in a spoonful. With such an abundance of meat in the bowl, one person could walk away satiated after a single serving. But we had just begun.

By contrast, Kirin's spring rolls were garden-variety, neither substandard nor standouts, and notable mainly for their large size. Stuffed with veggies, these hot and crispy rolls were served with the type of sweet-and-sour sauce and burning-hot mustard found in every Chinese restaurant. Spring-roll fans won't be disappointed.

A creature of habit, I ordered kung pao chicken ($8), which appeared as an enormous mound of bite-sized chicken pieces, peanuts, strips of green pepper, sliced water chestnuts and small, sinister-looking jalapeno slices. Stir-fried in a brown soy-based sauce that was sweet with sugar and sour with vinegar, the dish didn't live up to the menu's spicy description. Not even those suspicious jalapenos burned the tongue, but I didn't mind, even though I'm a fan of spicy-hot cooking. The combination of peanuts and chicken in this delicious sauce is a temptation whether served mild or spicy.

Another favorite, Mongolian beef ($8), was served as a similarly huge portion of sliced steak coated in a rich, brown marinade that combined soy sauce, hoisin sauce, rice vinegar and peanut oil. These were stir-fried with green pepper strips, shredded noodles, caramelized onions, chopped green onion and jalapeno peppers. Each mouthful combined the sweet and rich sauce with a variety of textures and occasional pinpoints of spicy heat.

By this stage, we weren't surprised to see the size of the platter piled high with mu shu pork ($8) that arrived at our table. Thin slices of pork were stir-fried with scrambled egg and cabbage that retained quite a bit of its crispness. This was accompanied by four very thin pancakes made of white flour. The diner assembles the final product by rolling the mu shu pork in a pancake along with a healthy drizzle of hoisin sauce. While the mu shu tasted fresh and satisfying, the pancakes seemed a bit stale, crumbling in the middle as we rolled them up.

Even though nothing indicates it on the outside of the restaurant, Kirin is a seafood establishment with an extensive selection. We tried the steamed rock cod, which is priced individually depending on the fish's size and type. For example, a small portion can cost as little as $16, while an order made with a large, live cod can run as much as $30. Kirin's presentation is dramatic, with the entire fish served — head, tail, fins and all. Be sure to ask the waiter to fillet it for you; otherwise you might miss some of this fabulous, delicate meat, which is steamed with water flavored with onion, ginger, soy sauce and oil.

The spiciest dish we encountered at Kirin, Szechwan-style prawns ($11), incorporated a healthy number of plump prawns with sliced onion and jalapeno peppers in a thick, almost gelatinous sweet-and-sour sauce jacked with dry chili power and a splash of tomato sauce. Served on a modestly sized platter (at least by Kirin's standards), this entree was nonetheless rich, satisfying, and perfect for two with rice.

Kirin clearly has a loyal clientele, since the place was hopping whenever we visited. While the service proved to be a bit impersonal and sometimes even brusque, the food, atmosphere and late-night hours are the magnets that lure hungry crowds.

Kirin Chinese Restaurant

485 Castro St., Mountain View

650-965-1059

Hours:

11 a.m. to midnight daily