Trendy Grill on the Park Takes Care With Its Cuisine : * THE GRILL ON THE PARK, 901 Fifth Ave., San Diego, 231-0055. Lunch and dinner daily. Credit cards accepted. Dinner for two, including a glass of wine each, tax and tip, about $35 to $70

It is said that a new broom sweeps clean. At the restaurant space in the Horton Park Plaza Hotel, the new broom wielded by The Grill on the Park has quite nearly obliterated any evidence of its predecessor, the Fifth Avenue Bistro.

The owners of the landmark building at Fifth Avenue and E Street, built early in this century as the city’s first skyscraper, expended a considerable sum in restoring the period elegance of the two-story banking hall. Their mistake was to install an uninspired menu and a so-so kitchen staff, with the result that the Bistro survived less than two years.

All new. All beautiful. All gone. The extravagance of the restaurant industry sometimes takes your breath away.

In the summer of 1989, Colorado restaurateurs Howard and Barbara Gunther and Stephanie and Michael Dietrich leased this Gaslamp Quarter space for a companion restaurant to their Aspen eatery, which is called The Inn on the Park.

Out went the elaborate, costly draperies that hung the length of the two-story windows. The original mosaic tile floor has been replaced by a new floor of patterned wood. The bar at the entry was yanked out and replaced by a gleaming exhibition kitchen; the new bar is on the mezzanine, which, just as in the days of the Bistro, is where you want to sit.

The mezzanine, although redecorated, retains a certain sense of sophistication, while the harshly redone ground floor room has all the charm of a school cafeteria.

The Grill on the Park attempts a rather sleek, ultra-contemporary appearance. The success of this is, at best, mixed. But there is a sort of hilarious appeal to the waiters’ black uniforms, which are brightened by multihued neckties of a pattern so wild that they seem salvaged from the psychedelic ‘60s.

The menu definitely is contemporary, which is to say that it offers currently popular categories of foods--pizzas, pastas, grilled fish, fowl and meats--and emphasizes sharp, definite flavors. It is an agreeable menu, if not particularly innovative, and the kitchen generally turns in an excellent performance.

Much homage is paid to trendiness. The very first listing seems a sort of nouvelle -California-Creole-Southwest cuisine combination, and you can’t get much trendier than a stew of those mixed styles--in this case a spicy black bean soup filled out with smoked pork and New Orleans-style andouille sausage. For that final gesture that adds a little je ne sais quoi of novelty, a spoonful of cilantro-spiked sour cream garnishes the soup.

The proprietors, evidently accustomed to satisfying appetites honed on the Aspen ski slopes, serve portions considerably larger than the San Diego norm. This makes the thought of a starter questionable--the entrees really are enormous--but one that works well on a shared basis is the fried onion loaf. This rectangular block of batter-crisped rings is served, a la Tony Roma’s rib restaurants, with a pitcher of barbecue sauce, and is equally happy as an auxiliary vegetable with the entrees.

Among other choices are tempura-fried zucchini slices with what the menu calls “buttermilk herb dipping sauce” (in its ingredients, this sounds suspiciously like “ranch” dressing); deviled lamb ribs with jalapeno pepper jelly; a skewer of mesquite-grilled steak chunks and shrimp served with a spicy, Thai-style peanut sauce, and Southwestern- nouvelle style crab cakes crusted with blue cornmeal and dressed with a chili-corn butter sauce.

The display kitchen includes the requisite wood-burning oven, and the pizzas that emerge from it are, in fact, quite superior--the thin, finely textured crusts delicious with their seasoning of olive oil and mixed fresh herbs. The choice includes a pie topped with barbecued chicken and cilantro, and a Mexican-style version with rock shrimp, salsa, sour cream and avocado, but the most elegant is the pizza dressed with roasted garlic puree, goat cheese and sun-dried tomatoes. This combination may be this era’s culinary equivalent of the pet rock, but it is undeniably irresistible.

The pasta list is somewhat more restrained (there is, however, angel hair pasta with something called “Cajun chicken”), and the likeliest sounding choice might be the lasagna stuffed with Maine lobster, cheese, mushrooms and spinach.

The kitchen does seem to take great care with the cooking of the entrees. One fish special, a filet of Norwegian salmon, was bedded on sauteed spinach, crusted with four types of peppercorns and sauced with a pale puree of yellow tomatoes and roasted garlic. It showed considerable imagination and had been treated with finesse; the beautifully moist fish flaked at the merest nudge of the fork.

The herbed, roasted chicken seemed almost to crackle on the plate, its skin a dark shade that promised a fine, crisp finish; the flesh, meanwhile, remained nicely juicy. A whole bird was served, not an enormous specimen but still sufficient for two diners, although it was served for just one; half of it went home for later consumption.

The barbecued baby back ribs (listed by the menu as “famous”) were good, if unexceptional, a comment that also could be made about the grilled, center-cut pork chops in a mustard-horseradish sauce. Other entree choices include a Yucatan-style chicken breast marinated in spiced fruit juices; a 1-pound veal chop and a simple New York sirloin with sauteed mushrooms. All of these are accompanied by a hillock of the day’s vegetable (on one occasion, quite respectable green beans amandine) and a choice of sliced tomatoes, french fries or the city’s largest stuffed baked potatoes. These spuds are creamy and well-seasoned, but utterly daunting in size.

Perhaps because of the menu’s generally spicy tone, the dessert list takes a very basic approach and limits itself to sundaes, a fruit plate and a low-slung creme brulee garnished with a side of mixed berries.