DINNER PREPARATIONS begin at 6 a.m., when Cowboy, Tom, Lynne and their Chevy van head for the surburban supermarkets. At the first stop, a Safeway, the shoppers are disappointed. Boxes are piled high in the dumpster and the only retrievable food is an unopened loaf of bread.

At store number two on the route, another Safeway, Cowboy has a better chance to practice his dumpster art. Covered in heavy overalls but not bothering with gloves, he hoists himself onto the rim of the metal bin a foot taller than he is. In he goes, feet first, heading for the corners and piling everything toward the middle as he excavates. At this stop the finds are better -- several heads of lettuce and almost a dozen tomatoes. The produce is not perfect and not pretty, but not rotten. It will all be washed two or three times and even if the tomatoes have become soft, they will be fine for stew.

The third stop on the seven-market route yields scavengers' gold. "Candy!" Cowboy shouts, as he throws out bag after bag of orange-coated jellied sweets. A dozen half gallons of milk, marked two days past the selling date, and some potatoes make this a fine discovery.

This is the start of a typical shopping spree for the volunteers from the Community for Creative Non-Violence (CCNV). Tonight, like every night, their dinner guests will be a hundred or more homeless streetpeople in Washington. And this morning, like every Monday and Friday morning, the hosts must look for food -- free food.

Holidays are not much different. Collecting the throwaways and giveaways that merchants can no longer sell will be the strategy for preparing Christmas Eve dinner, too, but holiday spirit usually brings heavier meat donations. With contributions from Washington Beef, tonight's everyday meal will turn out to be lamb stew. For Christmas there will be turkey, ham and ribs.

And the atmosphere for their second annual Christmas Eve dinner will also be different from the daily dinners. The rest of the year these homeless eat outside in an alley, but for Christmas Eve, the four or five hundred they expect will eat in a local church. From tables outlined with red ribbons and evergreen sprigs, the streetpeople will sing carols and watch a talent show performed by the regulars among them.

The daily dinners are served at the Drop-In Center, a project run by CCNV to provide food services to the homeless -- as well as laundry facilities, a shower room and a place to rest and talk. Like other soup kitchens, churches and charities that serve free dinners, the Drop-In Center depends on donations from organizations and individuals. But unlike the other groups, the Center does not use the Washington Food Bank, a branch of the Second Harvest National Food Bank Network, a nationwide organization funded by the government and foundation grants. Acting as a liason, the food banks distribute unsaleable and surplus food from supermarket chains and food companies to member charities.Because CCNV does not consider itself tax exempt (it does not believe in taxes), it does not qualify for food bank aid. Most of the donations at the food bank warehouses are packaged or canned items, and a director at the Washington branch admits that the selection of produce is not good.

Spokesmen from both Giant and Safeway supermarkets maintain that they just don't have a sizeable surplus of unsold produce. As for CCNV's collecting food from their dumpsters, they disapprove. "I was not aware of it," said Ernie Moore, public affairs manager at Safeway. "But we would object to it because the food might be contaminated." Public affairs director of Giant Foods, Barry Scher said, "Everything is thrown in there, it's just not a healthy environment."

The coordinator of the Drop-In Center claims they do not take from the dumpsters food that has gone bad and that they've never had a problem with sickness.

According to Herbert Wood, chief of Washington's Bureau of Occupational and Institutional Hygiene, the Center and some other soup kitchens have not been issued commercial licenses since their home-style kitchen equipment does not comply with the city's commercial standards. The Bureau encourages them to work up to those standards, though, and doesn't intend to try to close them down. "They've got the angels on their side," Wood said. So the scavenging efforts of the CCNV volunteers continue.

By 8:30 a.m. there are 10 cartons in the van, filled with boxes of cold cereal, corn on the cob, green peppers and cottage cheese.The cottage cheese, along with other dairy products found in the dumpster are, for safety's sake, cooked and incorporated into the stews, rather than being served right out of the containers.

Cooking dinner may take the rest of the day, so it must be started. On the way back the shoppers munch on perfectly edible peanut butter cups as Lynne recounts past food hunts: the time there were "five refrigerators full" at the Hampshire Open Air Market, the time someone almost angrily dumped Cowboy into the dumpster, the times there weren't any food.

When they arrive at the 12th Street house, the Center's headquarters across from the trailways bus station, the homeless there eagerly unload the goods. Back on the road -- this time with Carol as the "shopper," the next stop is the Florida Avenue wholesale markets. The coordinator of the Center, Carol lives there with her two children, aged 9 and 11. An ex-house wife and nursery school teacher, she is exuberant and dedicated. "I used to be married, and all the things I thought I'd miss, I'm doing here, except now I plan dinner parties every night -- and for 500 people."

At the wholesale markets, the pickups are prearranged. The tomatoes, cabbages, celery, spinach and even pomegranates, avocados and watermelons fill the van a second time. Because out-of-season fruits and vegetables are more sensitive to the cold weather and spoil more quickly, the Center is often given exotic produce. "One winter we had around $200 worth of strawberries," Carol recalls.

With donations from a local synagogue, Carol buys 123 pounds of chicken franks at Marlin's, which will be used for franks and beans. "Stop in for Christmas and we'll help out with the dinner!" one of the owners shouts, as she wheels out the meat.

In the Center's kitchen, a 13-gallon pot hovers on the burner, a yard-long spatula rests inside. The 12 or so pounds of lamb ribs boiling in the water will later be joined by rice and vegetables. The kitchen is tiny, with a refrigerator, a range, an unsteady wooden table and two sinks. Shelves line one wall, housing the slim sampling of canned goods.

Dave, an admittedly nervous cook, is the volunteer assigned to tonight's dinner. As he slowly washes and slices tomatoes for the salad, he is chided by Carlos, one of the homeless. "Dave's the only one who messes up the meal, 'cause he never cooks the same way twice." It's easy to understand why, since the cooks can never predict what food they'll get on a given day. Creative cookery must be practiced here, as it's hard to find recipes that call for ingredients like 100 overripe tomatoes or four cartons of pomegranates.

By 5 p.m. dinner is ready. Two pots of stew and two five-gallon buckets of limp salad are brought outside to the back alley where the homeless line up for the meal. The large portions of lamb stew fired with cayenne pepper are quickly eaten with plastic spoons. There are rolls and rye bread, day-old donations from Ottenberg's bakery.

Some of the streetpeople who were there last year talk about the Christmas dinner. "It was really beautiful," says one. "A lot of people haven't felt that way in a long time -- and it certainly filled up that hole in the stomach."