The fantasy: One rainy Tuesday afternoon when you don't feel like cooking, one of the great French chefs comes to your house to make dinner.

The reality: It's more like one of those nightmares in which you're taking an exam and your pencil keeps breaking.

Georges Blanc, chef-owner of La Me`re Blanc in Vonnas, one of France's 19 three-star restaurants, and the youngest chef to have garnered the honor, was in Washington to attend a reception at the White House (which was canceled) and promote his new book, "The Natural Cuisine of Georges Blanc" (Stewart, Tabori & Chang, 1987). He agreed to shop with me and demonstrate some recipes that could be made with only what was found in a local supermarket. The most convenient place we could cook was my house and that had the advantage of verifying that the recipes could be made in a home kitchen.

Blanc was to make potato crepes with salmon and lemon beurre blanc, his modernization of his grandmother's potato pancakes. The supermarket grapefruits inspired him to add grapefruit meringues. But there was no salmon caviar and fresh salmon was available only cut into steaks; he'd wanted fillets. Since there was no double cream or cre`me frai~che, Blanc decided to made do with sour cream in his recipe. Then, once I convinced him sweet butter had no sugar in it, we had what we needed.

We arrived home to find my son heating leftover pizza and spaghetti in the microwave. He rose to the occasion and offered some to Blanc, who in turn rose to the occasion and refused without wincing. Blanc did, however, wince when he found I had no steamer (thrown away after being bent in a jammed drawer). I fashioned a steamer by punching holes in an aluminum pie pan and perching it on a flan ring.

By that time Blanc was having more trouble than could be blamed on my kitchen; he was developing a flu, he thought, and needed aspirin. Nevertheless, he put on his chef coat and asked for an apron. (I managed to produce a white one, though it said, "Dinner at Julia's".)

Blanc was pleased that I had a scale to weigh the potatoes, and my dull knives didn't daunt him. He peeled 2 1/2 pounds of potatoes in no time and set them to steam, then to cool (his grandmother had developed the recipe as a use for leftover mashed potatoes).

The second grater I produced had the right size holes for grating lemons. And my penknife yielded a tweezer for picking the bones from the salmon. Unable to find a potato masher, I did miraculously uncover a ricer. Next he turned to dessert -- grapefruit covered with meringue.

Sure I had a pastry bag. Who would be without a pastry bag? The only problem was I couldn't find it. I did find a friend who could find hers, though.

Did I have a tomato? Of course. Well, actually only half a tomato.

Suddenly I saw my kitchenware for what it was. Chipped bowls. Enameled pots with scarred bottoms. Battered pans that had seen me through college. Even my fabulous KitchenAid stove top was way too tame for him.

Please pass the dill, Blanc asked. I reached for the jar of dill. No, he meant fresh. Fresh out, I confessed. Parsley? There I was okay. I had a mountain of parsley.

Next I had to produce some photogenic dinner plates. Certainly those I'd bought in Paris would do. No, too decorative. Blanc wanted plain white, and didn't seem to mind that my plain ones were stoneware and slightly crazed. He set his delicately browned potato crepes on a plate, decorated it with four tiny diamonds of skinned, seeded tomato and two wisps of parsley, spooned on lemon beurre blanc, arranged meringue-topped grapefruits and smiled for the photographer.

Then we all ate. I even managed to produce a mildly respectable bottle of wine (red, since I had no white chilled).

Had Blanc ever cooked in more difficult circumstances? He smiled enigmatically. Anyway, I consoled myself, my kitchen was sufficient to produce exquisite potato pancakes with lemon beurre blanc.

GEORGES BLANC'S POTATO CREPES WITH SALMON AND LEMON BUTTER SAUCE (8 servings)

1 pound mashed potatoes, room temperature

2 tablespoons milk

Salt to taste

1/2 cup plus 2 tablespoons flour

3 eggs

4 egg whites, unbeaten

1/3 cup sour cream, approximately

1 cup clarified butter, approximately, for frying

1 pound raw or smoked salmon, sliced

FOR THE BUTTER SAUCE:

1 1/2 sticks (12 tablespoons) cold unsalted butter

1 teaspoon grated lemon rind

1/4 cup water

1/2 teaspoon salt

Freshly ground pepper to taste

1 tablespoon lemon juice

Steam potatoes; boiling them might make them too watery. Mash them smooth and beat in milk and salt to taste. Set aside to cool or, better yet, refrigerate overnight and bring to room temperature when preparing batter.

Gradually mix flour into potatoes. Add eggs, one at a time, then unbeaten whites. Gradually stir in sour cream, adding only enough to thin the batter so it barely flows. Do not beat. Batter can be refrigerated, then brought to room temperature for cooking.

To make the sauce, cut butter into tablespoons. Cover grated lemon rind with water in a small saucepan and bring to a boil. Drain well. Mix rind with 1/4 cup fresh water, salt and pepper; bring to a boil and reduce to 2 tablespoons. Adjust heat to medium-high and whisk in butter one tablespoon at a time, adding next tablespoon quickly so butter doesn't melt but stays creamy. You may not need the last tablespoon or two; stop when sauce is slightly thickened. Remove from stove and add lemon juice. Adjust seasoning and add more juice if necessary. Set aside in a slightly warm place.

To cook pancakes, heat a heavy skillet with 1/4 inch clarified butter over a hot fire. When butter is smoking, spoon in batter to form silver-dollar-size pancakes. They should puff to about 1/4 inch thick. If too thick, thin batter with sour cream a little at a time.

As pancakes cook, arrange a small slice of salmon on uncooked surface of each. When bottom is browned, turn pancakes so salmon is on the bottom, and brown that side. Keep pancakes warm while cooking remaining pancakes.

Arrange pancakes, salmon side down, on plates and spoon on sauce. Serve as an appetizer.

Variations: Serve plain pancakes as a vegetable. Or sandwich thin slices of salmon with salmon caviar before putting on pancakes. Other toppings (most elegantly, truffles) can substitute for salmon. For dessert, serve pancakes with sugar and cinnamon.