The table is still set in the dining room at Hillwood. Marjorie Merriweather Post's mansion, at the edge of Rock Creek Park in W ashington, has been a museum since her death in 1973, and ever since then, the 29-foot dining table has been ready for a dinner that is never to be served.

The 40 rooms are said to house the most representative collection of Russian decorative art outside of the Kremlin, as well as an astonishing collection of French 18th-century furniture and china. And while Marjorie Merriweather Post -- the Post Toasties heiress, as she was called -- lived there, the roomfuls of Faberge' and Se vres, the malachite and lapis lazuli were in regular use. The 4,000-pound inlaid marble dining table could be set dozens of different ways before the Post household would have to repeat a china pattern.

Nowadays the table may be covered with lace, with robin's-egg blue and gold china, even with fresh flowers; but Post's will forbids food or drink to ever again be prepared or served in the house.

So visitors are bound to get hungry, particularly after a two-hour tour of the house and a couple hours more of wandering through the gardens, the dacha and various other little buildings that add up to the 25-acre estate.

Thus the directors of the museum, considering the sense of graciousness such a collection depicts, decided it was appropriate to feed those hundred or more guests a day -- just as its Washington neighbor, the Phillips Gallery, decided to do when it invited Suzanne's restaurant to open a small cafe in its basement earlier this year.

This is an era, after all, when food is a major artistic realm. Vice presidents have cooked in public, celebrities compete in the kitchens at charity balls, entire resort hotels are turned over for the weekend to the discussion and consumption of chocolate. Food is entertainment, food is social status, food is political currency. And the lack of food was seen as a disruption of the appreciation of this brilliant collection.

Setting up a cafe actually took a year. The estate's stable -- which had been turned into a garage -- had to be torn apart and redone. And its style had to fit Hillwood's. The walls are stark white, punctuated with small gables and windows and, at the center of the ceiling, a tiny cupola with a skylight. The tables are simulated marble in a shade that food people might call aubergine but at Hillwood is known as royal purple. China, tables, chairs, all had to be coordinated. Since the museum allows 100 people a day to tour the house (reservations are backed up for six weeks, and spring reservations are already solidly booked), and the gardens are open to anyone who pays the $2 fee, the cafe had to accommodate a substantial number -- about 48, as it turns out.

Caterers were invited to audition, and Movable Feast was chosen. The kitchen was designed to its specifications, a small "finishing kitchen," since the main preparation is to be done at Movable Feast's headquarters a couple miles up Connecticut Avenue. Continental breakfast -- featuring Movable Feast's much-admired scones -- is to be served, as well as afternoon tea and, of course, lunch. Flowers are be provided by the estate's own greenhouse, and when orchids are in supply they will certainly show up on the tables. As for the menu, it is geared towards a clientele who "expect a certain standard after going through that house," as one of the museum officers put it. Menus are on a two-week rotation (so the staff aren't likely to grow bored with the selection), including cold salads, soups, hot main dishes and plenty of pastries. Unlike anything else visitors will see at Hillwood, the foods will be available to take home.

Movable Feast considered serving some Russian foods to coordinate with the collection's theme, but owner Stacy DeLano -- who became a caterer 10 years ago after working in Asian foreign policy at Brookings Institution and then ran a plant business -- worried that might seem too cute. She is, however, working on a signature dessert for Hillwood. In the meantime, two signatures of her catering company, smoked salmon cheesecake and flank steak salad, are on the menu.

The Hillwood cafe is open when the museum is open, which is every day but Sundays and Tuesdays, from 9 a.m. to 4:30 p.m. They are also closed in February. Tabletalk

*With airport security being intensified throughout the world, no potential danger is being overlooked. Thus the following sign in the Benares, India, airport: "No guns. No knives. No red chili powder."

*Speaking of signs, I miss the one in St. Louis, at the corner of Carr Lane and Chouteau, which has been destroyed by fire. Painted on the brick wall was a huge arrow and the text, "Brains 25 . Drive In."

*The best suggestion in this week's mail was for six-sided uncrushable containers for packaging soft fruits such as strawberries, blueberries, peaches and plums. Perhaps something akin to an egg carton. MOVABLE FEAST'S FLANK STEAK SALAD (15 servings)

2 1/2 pounds flank steak

FOR THE MARINADE:

1/2 cup olive oil

1/4 cup soy oil

1/2 cup red wine vinegar

1 tablespoon lime juice

1 tablespoon oregano

1 tablespoon thyme

1/4 cup brown sugar

1 tablespoon oriental chili sauce

1/4 cup teriyaki sauce

FOR THE SALAD:

1 1/2 pounds onions, julienned

1 1/2 pounds red bell peppers, julienned

1 1/2 pounds green peppers, julienned

1 1/2 pounds new red potatoes, halved lengthwise and sliced widthwise to a 1/4-inch thickness

1 tablespoon rosemary

1 tablespoon salt

3/4 tablepsoon pepper

FOR THE DRESSING:

1/2 cup soy oil

6 tablespoons red wine vinegar

1/2 tablespoon salt

1/2 tablespoon rosemary

3/4 tablespoon garlic, minced

Trim flank steak, and cut across the grain into 4-inch-wide pieces. Combine marinade ingredients and add flank steak, turning to coat well. Marinate in refrigerator overnight.

Spread onions, red and green peppers in a shallow pan large enough to hold them in one layer. Spread potatoes in another shallow pan in one layer. Sprinkle rosemary, salt and pepper over all. Put both pans in a 400-degree oven. Remove onions and peppers after 15 minutes and set aside to cool. After 5 minutes more remove potatoes from oven and set aside to cool.

In a hot ungreased frying pan cook flank steak to medium-rare doneness. Slice it diagonally, against the grain, 1/4-inch thick.

Combine flank steak and vegetables.

Mix ingredients for the dressing in a separate container. Pour dressing over the salad mixture and mix together well. Serve at room temperature.