Why is it that a few outstanding dishes are unforgettable? Often they are nothing fancy -- a fragrant soup perhaps, or a salad of the freshest tomatoes with just the right touch of olive oil and herbs. And what better time than Thanksgiving for a nostalgic backward glance? This collection adds up to a menu of memorable first and last courses to surround the Thanksgiving turkey, with a couple of vegetable accompaniments.

Dinner opens with a cream of oyster soup, a chance to taste oysters away from the turkey stuffing. When I first tasted this soup on Virginia's Chincoteague Island, wildlife refuge and home to oysters of renown, I could not believe the simplicity of the recipe. But the elderly cook patiently repeated her formula and I've found the sea-salt flavor of oysters, complemented by cream, comes through every time. A real taste of the Eastern Shore.

Never would I suggest deviating from plain roast turkey on the Thanksgiving table, but accompaniments are another matter. This squash pie with its underpinnings of leek, parmesan cheese and garlic evolved during the summer, after a talk with the proprietor of the roadside fruit stand near our cabin in West Virginia. I've always found squash to be bland, but not this version. Canned pure'ed pumpkin is an easy alternative to fresh squash.

From the sophistication of San Francisco comes a perfumed vegetable ragout created by Jeremiah Tower, one of the stars of the new California cuisine (his restaurant is called, appropriately, "Stars"). Recently when Tower and I were demonstrating cooking side by side, he extolled the virtues of simple butters like this one, musky with wild mushrooms. How right he is -- the combination with roast turkey is sublime.

Lastly we take a supersonic flight to Australia to tuck in to pavlova -- a giant crisp meringue with a melting heart of marshmallow. Pavlova was introduced to our family by Australian Prue McCoy, who for one happy summer sustained our table with similar delights. McCoy filled her pavlova with tropical fruits and cream, but here I've added tart cre`me frai~che and a compote of cranberries, the crowning festive fruit.

Timetable All time-consuming preparation for dinner is completed ahead, so dishes need only to be reheated and plated for serving.

Up to one week ahead: Make pavlova.

Up to two days ahead: Make soup but do not add oysters. Make mushroom butter for vegetables. Cook cranberries for pavlova.

Up to one day ahead: Bake squash pie. Chill the wine.

Two hours before serving: Cook vegetables for ragout. Add cranberries to pavlova.

Ten minutes before serving. Reheat oyster soup, add oysters, cream and parsely.

Just before serving: Warm squash pie in a low oven.

After serving soup: Reheat vegetable ragout and add butter. CREAM OF OYSTER SOUP (10 servings)

Fresh mussels, cooked in a covered pan over high heat until open, then removed from their shells, can be substituted for oysters.

1/2 cup (1 stick) butter

2 shallots, finely chopped

1/2 cup flour

3 cups light chicken stock

8-ounce bottle clam juice

1/2 teaspoon dried thyme

1/2 teaspoon dried tarragon

1 bay leaf

Salt and pepper to taste

1 pint shucked medium oysters, cut in half, with liquor

1/2 cup whipping cream

2 tablespoons chopped parsley

Oyster crackers for serving

In a large saucepan, melt butter and saute' shallots until soft. Whisk in flour and cool until foaming. Whisk in chicken stock and clam juice and bring soup to a boil, whisking constantly. Add thyme, tarragon, bay leaf and salt and pepper to taste and simmer 5 minutes. Soup can be prepared up to 2 days ahead and refrigerated.

To finish: bring soup to a boil, stirring. Add oysters with their liquor and cool 1 minute. Add cream and parsley and bring just back to a boil. Discard bay leaf and taste soup for seasoning. Spoon it into bowls and serve oyster crackers separately.

WEST VIRGINIA SQUASH PIE (10 servings)

An excellent opening to a meal as well as accompaniment to the roast bird.

2 tablespoons butter

4 leeks, white and tender green parts, thinly sliced

2 garlic cloves, finely chopped

Salt and pepper to taste

2 pounds winter squash, cut in cubes with peel and seeds discarded

3 cups whipping cream

4 eggs, beaten to mix

1 cup grated parmesan cheese

1/4 teaspoon grated nutmeg

In a saucepan, melt butter, add leeks, garlic, salt and pepper and press a piece of foil on top. Add the lid and cook very gently, stirring occasionally, until leeks are soft, about 20 minutes. Do not let them brown.

Put squash in a large pan of boiling salted water and simmer 10 to 15 minutes until very tender. Drain thoroughly, then crush with a potato masher or fork. Stir together the squash, cream, eggs, cheese and nutmeg with salt and pepper to taste.

Spread leeks in two 9-inch unbaked pie shells and pour squash mixture on top. Bake pies at 425 degrees for 10 minutes. Lower heat to 350 degrees and continue baking 40 to 50 minutes longer until filling has set. Squash pie can be refrigerated up to a day. Warm it in a low oven just before serving.

VEGETABLE RAGOUT WITH WILD MUSHROOM BUTTER (10 servings)

Choose a wide selection of vegetables, the more colorful the better. With care, they can be cooked ahead for reheating.

FOR THE MUSHROOM BUTTER:

1 ounce dried mushrooms (ce`pes, morels, or chinese black mushrooms)

1 cup (2 sticks) butter

FOR THE RAGOUT:

1 sprig fresh rosemary or 2 teaspoons dried rosemary

Salt and pepper to taste

20 pearl onions, peeled

2 bunches broccoli, flowerets separated, stalks peeled and thinly sliced

1 pound carrots, thinly sliced

2 red bell peppers, cored, seeded and cut into strips

1 head radicchioSTART NOTE cq END NOTE, shredded (optional)

For the mushroom butter: soak mushrooms in hot water to cover 15 minutes or until soft. Drain them, reserving liquid, and squeeze them dry. Wash mushrooms well and, if stems are tough, discard them. In a food processor or blender, cream butter. Add mushrooms and 1 tablespoon reserved liquid and work until smooth. Butter can be refrigerated up to 2 days.

To cook the vegetables: in a large skillet, bring 1 cup reserved soaking liquid to a boil with rosemary, salt and pepper. Add onions, cover, and simmer until barely tender, about 5 minutes. Add broccoli stalks and carrots and cook, covered, until carrots are tender, about 5 minutes more. Finally, add broccoli flowerets and peppers and cook until both are nearly tender, about 2 minutes. Vegetables can be cooked up to 2 hours ahead.

Just before serving, reheat vegetables on top of stove. Add butter, in pieces, tossing vegetables to coat them. Stir in radicchio if using, season ragout to taste and serve at once.

CRANBERRY PAVLOVA (10 servings)

A meringue dessert from Australia, where dancer Anna Pavlova achieved stardom.

FOR THE MERINGUE:

8 egg whites

2 1/2 cups sugar

1 1/2 tablespoons cornstarch

1 1/2 teaspoons distilled white vinegar

FOR THE FILLING:

3/4 pound fresh cranberries

1 cup sugar

Grated zest and juice 2 oranges

1 cup cre`me frai~che, or 1 cup whipping cream, stiffly whipped

Butter and flour a baking sheet, discarding excess, or line it with nonstick silicone paper. Mark a 12-inch circle using a flan ring or pan lid.

For the meringue: stiffly whip egg whites, add 1/3 cup sugar and continue whipping 30 seconds until the mixture is glossy and forms long peaks. Sift cornstarch with remaining sugar. Fold sugar into egg whites, followed by vinegar. Pile mixture on the marked baking sheet and spread into a round, hollowing the center slightly.

Bake pavlova in a 250-degree oven until cream colored and firm but still soft inside, 1 1/4 to 1 1/2 hours. Pavlova will crisp as it cools. Note: If it starts to brown during cooking, lower oven heat and cover pavlova loosely with foil. Let pavlova cool to lukewarm, then lift it off the baking sheet or peel off paper. It can be stored up to a week in an airtight container, or frozen.

To cook the cranberries: in a saucepan, mix cranberries with sugar, orange zest and juice. Cook, stirring often, until berries start to pop, 3 to 5 minutes. Let cool. Cranberries can be refrigerated up to 2 days.

To finish: not more than 2 hours before serving, set pavlova on a tray or large platter. Spread cre`me frai~che or whipped cream in the center and pile cranberries on top. Chill until ready to serve.