THEY SAID it couldn't be done, gathering the French chefs of Washington for a sociable lunch. What it took was about a carload of imported goose liver, provided by France's Grimaud Co. and prepared by Jean-Louis Palladin at Jean-Louis restaurant. Fourteen chefs came, some of whom had not even met each other before. Even more startling was that a woman chef -- Nora Pouillon of Nora's restaurant -- was included, and two Americans -- Mark Caraluzzi of American Cafe and Douglas McNeill of the Four Seasons -- neither of whom showed up.

The menu was foie gras (as a terrine layered with red and green noodles), more foie gras (sauteed with pears) and veal pot au feu (for a change of pace). Conversation centered on business, with the Jockey Club's Jean-Claude Galan complaining because he has too much business, which is like complaining about having too much foie gras. Lest anyone think the good life a thing of the past, Jean-Pierre Goyenvalle of Le Lion d'Or claimed that a major cause of accidental eye injury in this country is from popping champagne corks. Lunch ended with a guessing game, as people gradually realized that the puzzling flavor in the dessert -- praline layered with whipped cream and strawberries -- was chopped fresh basil.

California has piled our plates with avocados and alfalfa sprouts, but Florida is upstaging them. This year's food fad -- already outdistancing the Pistachio-Pudding Watergate Cake -- is called "Better Than Sex Cake," which may account for its sweeping the Midwest (last sighted by another Post editor at dinner in Cedar Rapids). Reports of the cake, or at least of recipes traveling under that name, have been heard throughout the Corn Belt.

The Florida version, claiming to be the original, directs that you bake a yellow cake in a 9-by-13-inch pan, then bring to a boil crushed pineapple and sugar, poke holes in the cake and pour in the pineapple syrup. Top with vanilla pudding, cover tightly and store overnight in the refrigerator. When ready to serve, cover with whipped cream (whipped "topping" if you want to be authentic) and coconut. What do you serve with it? "Strip and Go Naked Punch," of course, which in Florida is one part lemonade, one part vodka or rum and one part beer. Even celibacy sounds better to us, so don't expect us to test these recipes, reprint them or give them out over the phone. Nor do we intend to devise a diet version. We remain faithful to alfalfa sprouts.

What goes up does not always come down, but for one night it will at Trader Vic's. Next Tuesday, June 16, is that restaurant's 20th anniversary, and for that evening dinner will feature its 1961 menu and prices: filet mignon for $6.50 (nowadays $15.50), soft-shell crabs for $3.95 (now $12.25), lobster thermidor for $6.75 (now $18.25). No less startling is the difference in menu prose from the days before "truth in menus" enforcement. Since 1961, "Boston sole" has become just "sole"; "cubes of fresh Florida snapper" are now "cubes of snapper"; and "Mahi Mahi from Honolulu" is "Mahi Mahi from the Pacific." The lobster meat and vegetables are no longer designated as fresh, nor are the egg noodles. Of course, for that one night, getting a reservation is bound to be just as difficult as it was in 1961, when Trader Vic's opening was a major event in Washington.

New York must be saturated with French and Italian chefs, for now it is importing Baltimoreans. The most notable immigrant is Patrick McDonnell, who cooked at Baltimore's Prime Rib, Milton Inn and Chambord before opening the Sarabande in Towson, then the Black Pearl in Harborplace. He's taken his flower-decked plates and his Duck with Red Fruits to Manhattan's Le Coup de Fusil, which once launched a Washington notable, Le Pavillon's Yannick Cam. The Baltimore Connection also includes Pierre LeBlanc, former maitre d'hotel at Chambord and a chef at Sarabande, now at New York's Devon House; and Jim Pender, formerly second chef at Baltimore's Brass Elephant and now second chef at New York's La Tulipe.

Summer heat is so inescapable a focus in Washington that even serious journals such as Science 81 are compelled to deal with it. Thus, the July-August issue features "The Cold Facts About Ice Cream," the most startling of which is that Philip G. Kenney, ice cream technologist (will specialties never cease to amaze?) at Pennsylvania State University, calls ice cream "the sewage treatment plant of the cheese industry." He explains: Whey, the cloudy, bluish fluid that is left over when milk is made into cheese, was long dumped down drains to flow into rivers and streams. But in the last two decades, water pollution laws have required treating the whey before dumping, an expensive process. Cheese companies have found it easier to dry the whey and sell it to ice cream manufacturers for increasing the milk solids content of their products. Thus, cheap waste disposal becomes a cheap way to meet the milk-solids minimum requirements for ice cream. Added Kenney, "Nobody uses whey for positive reasons."

A note to Campbell's, on contemplating its Oriental soup line (wonton, Oriental chicken and beef teriyaki): When are you going to expand your alphabet soup line to include Chinese, or at least Greek?