IT'S THE CHANCE of a lifetime," said Joan Shih as she collapsed on the nearest chair, tiny beads of perspiration glistening on her nose. Shih had gone to bed at 4 Labor Day morning and was back in the kitchen by 7 a.m. When she finally sat down it was 3 in the afternoon.

And that was only the first day. There were to be 13 more like it. "No, they won't be this bad," Shih said, still smiling from underneath her net cap, used to keep her hair from falling into the food she and her cooking students were preparing for a group of 74 persons. It was not just any group of visiting firemen, but the Chinese performers of the Peking Opera, who are appearing at the Kennedy Center through Sept. 14.

The famished troupe had just arrived in Washington from New Jersey, and before they went to their rooms they descended on the dining room of the Diplomat Motel. This may be as unlikely a spot as you will find for theater performers. Located on New York Avenue NE, the truck route to and from Baltimore, the motel is surrounded by warehouses and gas stations. But inside it looks like any other inexpensive motel, and out back there is a swimming pool in the midst of an expanse of green lawn. It would be almost pastoral, if it weren't for the sound of Amtrak trains just beyond the pool.

For the Chinese, the Diplomat is a lot less expensive than the Watergate, or even the Holiday Inn in Georgetown. Futhermore, the motel's dining room, which once featured Chinese food, has been closed for several months. In one way that made it easy for Shih to set up shop; in another it made it more difficult. A commercial kitchen needs a lot of work to make it functional after months of disuse. (On Wednesday the performers moved down the road to the Quality Inn -- reason unknown -- but will continue to take their meals at the Diplomat.)

By Aug. 29 everything was ready to go. Shih had been preparing and freezing some food over the summer at her Rockville cooking school, Chinese Cookery. Last Sunday, along with her husband, Kenneth Carducci, their two daughters and assorted helpers, she began moving in utensils, serving pieces, dishes and food. They soon began the time-consuming cutting, slicing, mincing and chopping for the first meal and finished at 4 the next morining. It was to be an eight-course banquet featuring dishes from various regions of China.

The performers were expected to sit down at 1 p.m., but they couldn't wait. They had devoured the cold appetizers by 12:35, before the kitchen had a chance to finish frying two kinds of pork-stuffed egg rolls, not to mention the wontons (a late addition to the menu for the table of Chinese Moslems who do not eat pork and about whom Shih knew nothing until the last minute). She had also made moo shi pork.

A number of the performers had to leave for a press conference before the meal was half over. They were served crispy duck and sweet and sour shrimp but missed out on the moo shi pork, soup, eight jewels rice pudding, almond cookies, fruit and Mongolian lamb. The lamb should have been suitable for the Moslems, but it contained hot red peppers and green onions, neither of which they would eat. Shih didn't find out until it was too late.

Considering the logistics of trying to plan two weeks' worth of meals in Washington for a large group coming from Peking while working through a third party in New York, Shih, a native of Taiwan, is doing remarkably well. After the first meal members of the troupe pronounced it "much better than New York or New Jersey," where their cross-country tour began.

"It's much better if you can get someone to come to cater," explained the American tour director. "They don't actually dislike American food if it's prepared to their taste -- fried chicken, fried shrimp, preferably in peanut oil." As it turns out, they even like hamburger.

Hamburgers are one of the items on the 5 p.m., almost all-American snack menu, for which Shih and her rotating body of 30 helpers are also preparing barbecued chicken and ribs, steak sandwiches (with the American white bread on the side), cakes, cookies, tea, coffee and hot milk -- plus fried noodles and fried rice.

There is an all-Chinese brunch at 11:30 -- four dishes and soup -- and another meal after the performance at 11 p.m. that consists of four dishes and one soup but lots more of everything, plus tea, hot milk and a little beer.

Acrobats eat a lot, and if you've seen the energy they expend when they perform, you will understand why. Shih says they eat "triple the amount of an average American." Shih has recruited "for the minimum wage and the experience" a number of her present cooking class students and some graduates to cook and serve. One is so excited he has taken a two-week leave of absence from his job as a pharmaceutical salesman.Ed Crowley will be on hand every day because "it's exciting to show another culture Americans can do these things, too," he said.

Dorothae Harris, who was given the cooking classes as a birthday present by her daughter, plans to work all day long for seven days. Glen Brown, who is with Ingersoll Rand in public affairs, is coming in every night. A Chinese-American friend of Shih's from Rochester, N.Y., where Shih was a graduate student in chemistry, has taken her vacation to help out.

"I think we're doing it more out of fun," Harris said, and for the leftovers to which the 10-person crew finally sat down on Monday, after the performers had gone to their rooms. They are devoted students. "Joan's recipes are foolproof," said one. "The only problem is her classes ruin you for restaurants. I spent two weeks in China and I think Joan's food is better."

Shih has been teaching for nine years. A week after her stint as a caterer she begins her fall session.

Would she do this again?


A laugh. A pause.

"But it is a special honor." MONGOLIAN LAMB WITH HOT SAUCE

The essence of making this dish superb is that lamb should be sliced very thin and cooked rapidly. 3/4 pound leg of lamb, frozen or well chilled. Marinade: 1 tablespoon rice wine, or pale dry sherry 2 tablespoons dark soy sauce 1 tablespoon corn starch 1/2 teaspoon salt 1 teaspoon sugar, or honey 1/2 teaspoon Sichuan flower pepper, crushed 1 teaspoon vegetable oil Enough oil for deep-frying (6 cups if using a 14-inch wok), plus 2 tablespoons (peanut preferred) 2 leeks, or 4 green onions 4 cloves of garlic, minced 2 red chili peppers 1/4 cup bamboo shoots, sliced Seasoning Sauce: 1/2 tablespoon hot bean sauce 1/2 tablespoon dark soy sauce 1 tablespoon rice vinegar 1 teaspoon sugar 1 teaspoon sesame oil

Slice the partially thawed lamb into 1/8-inch-by-1 1/2-inch-by-3/4 inch pieces. Mix marinade, and soak lamb slices in it for 15 minutes. Pour 1 teaspoon oil on top to prevent from drying. Slice leeks or green onions into 1 1/2 inch long and 1/3 inch wide shreds. Mince garlic and slice bamboo shoots into pieces the same size as pork. Cut the ends of red peppers and tap the seeds out. Mix seasoning sauce well.

Preheat deep-frying oil to 375 degrees. Add lamb, stir and deep-fry very briefly. Remove. Heat wok, add 2 tablespoons fresh oil and stir-fry garlic, white shreads of green onions or leeks and red peppers until fragrant. Then add bamboo shoots, seasoning sauce, and lamb. Keep stir-frying briskly while adding green onions. Turn off heat when completely blended. Serve at once. FRAGRANT CRISPY DUCK

In order to give a finished duck very light, crispy skin and fragrant meat, it requires long and careful preparation. Soaking (marinating) and drying are essential in the making process. Traditionally Crispy Duck is served with flower pepper salt and lotus leaf buns. 1 duck Mix #1 5 slices fresh ginger root, minced 3 green onions, finely diced 2 tablespoons salt 1 tablespoon Sichuan flower pepper, crushed 2 tablespoons rice wine or pale dry sherry 4 star anise, crushed 1 tablespoon sweet fennel (optional) Mix #2: 3 tablespoons soy sauce 1 tablespoon rice wine or pale dry sherry Mix #3: 1/4 cup cornstarch 1/4 cup waterchestnut powder Mix for dipping: 1 tablespoon salt 1 tablespoon crushed flower pepper 6 to 8 cups peanut oil for deep-frying Lotus leaf buns (available in Chinese market)

Clean, wash, and pat dry the inside and outside of duck. Hang duck up by the tail and dry in cool air for 2 hours, or use an electric fan to blow-dry for 30 minutes. Prepare marinade mix 1: crush flower pepper and star anise by a mortar and a pestle. Rub the mixture all over the duck, inside and outside, let stand for 30 minutes. Place the duck in a steamer and cook over simmering water for 1 1/2 hours or until very soft.

Remove and cool the duck. Cut the duck in half down the breastbone and along the backbone. Rub with Mix 2, then roll in Mix 3. Heat oil to 400 degrees. Deep-fry duck briefly and then turn down medium heat. Continue frying until golden brow. Remove.

Cool on paper towel slightly and use a cleaver to cut duck into bite-sized pieces. Place duck pieces back to a shape of whole duck in a platter and decorate with thin slices of tomato and shreds of lettuce. Serve with lotus leaf buns, hoisin or sweet bean dip sauce, and flower pepper salt made by mixing salt with crushed flower pepper.