RESTAURANT REVIEW : Westlake’s Tiny Takahashi Has Big Appetite for Exotic : Some of the standouts are fresh sea urchin, green mussels in sake, and sea bass in sweet eel sauce.

With a population of more than 125 million crowded onto a group of islands equal in area to California, the Japanese don’t seem to mind sharing small areas--as evidenced by their willingness to allow “packers” (who politely wear white gloves) to wedge them into subway cars during Tokyo’s rush hour.

So it’s not surprising to discover tiny Takahashi, a Japanese restaurant in Westlake’s North Ranch Mall. The narrow storefront room consists of a 16-seat sushi bar and four tables. I personally like the coziness of the place, but the big liability is that at peak lunch and dinner hours, I am forced to wait. This can be excruciating if I’m enormously hungry and can only watch as tantalizing treats are made by the good-natured sushi-sans, and other attractive foods are brought out of the kitchen.

When I’m finally seated and relaxed from a few sips of warm sake or icy Japanese beer, I like to start with sushi. Among the more unusual items I’ve tried are the fat American roll filled with scallops, shrimp and crab ($5.50), the Tokyo roll with tuna and puckery pickled daikon ($4.50), fried green beans and shrimp roll ($4.50), and an unctuously rich eel and avocado roll ($5.50).

Admirers of sea urchin will flip over the pristinely fresh uni ($5.50) that was plucked hours earlier from the waters off Santa Barbara. If you’re feeling flush, try the sweet shrimp ($9), which is served in two courses: the raw shrimp tails are served as sushi, and the heads are deep-fried into a mouthful of pure crunch.

But there’s so much more fascinating food here besides sushi. I have easily made a complete meal out of a number of small dishes (which the Japanese call kappo ). Try an order of baked shrimp, scallops and shimeji mushrooms ($6.50) in a rich scallion and mayonnaise sauce. Or nuggets of moist baked halibut topped with cooked salmon and a dollop of cream sauce ($6.50). Or plump green mussels ($3.50) baked in sake.

Other petite plates that excited my taste buds include crunchy deep-fried chicken ($5.50) marinated in sake and garlic, baked marinated Chilean sea bass ($6.50) in a sweet eel sauce, crackling chunks of fried eel and tofu ($5.95), baked slices of sweet Japanese eggplant ($4.95) in a miso sauce, and garlicky baked shimeji mushrooms ($3.95).

But there are some detractors. Chicken yakitori sticks ($5.50) were too dry, and shrimp and vegetable tempura ($5.50) suffered from a case of the blahs. While sauteed mushrooms and giant clam ($8.95) had a nice marinade sauce, the clam was tough and stringy.

Spicy tuna salad ($5.95) is a large bowl of baby greens topped with a piquant mound of tuna in a fiery sauce. Salmon skin salad ($5.50) combines greens with shards of crispy salmon skin, scallions and chopped goboh (wild ginger root) in a ponzu -based dressing. The latter veers on the salty side, which can be easily remedied by another sip of cold beer.

Vegetarians will appreciate either the combination of enoki and shimeji mushrooms ($5.50) in a soy vinaigrette or the tangy radish sprout and enoki mushrooms ($4.50) combo.

Having visited most of the major cities in Japan, I have never seen anything as exotic as the apricot salad ($7.50), which brings together slices of tuna, halibut, albacore and octopus with chunks of avocado, daikon, sprouts and apricots. The soy-based dressing has a soupcon of Tabasco, which permits this glorious salad to offer a lively juxtaposition of sweet, sour and spicy flavors.

If you opt for a dinner entree, you’ll be happy with chicken teriyaki ($10.25), which is freshly char-grilled. More unusual is the chicken misoyaki ($11), which pairs a lively soy bean paste sauce with slices of broiled chicken. I’m also an enormous fan of the Chilean sea bass teriyaki ($14), one succulent piece of fish.

Every dish in this establishment is beautifully garnished with fruit and vegetables, catering as much to the eye as to the palate. This little jewel of a restaurant turns its cuisine into miniature pieces of edible art.

Details

* WHAT: Takahashi Japanese Restaurant.

* WHEN: Tuesday-Friday, 11:30 a.m. to 2:30 p.m.; Tuesday-Sunday, 5:30-10 p.m.

* WHERE: 3835 E. Thousand Oaks Blvd. (North Ranch Mall), Westlake.

* HOW MUCH: Meal for two, food only $25-$50.

* FYI: All major credit cards; beer and sake.

* CALL: 496-5294.