SOUP IN A PUMPKIN

IN her new cookbook, Julia Child adds a warning to this recipe. ``This is a delightful beginning to any fall dinner, particularly the Thanksgiving feast. But be sure to choose a pumpkin that will fit your oven - or vice versa!'' 2 1/2 cups lightly pressed fresh crumbs of homemade white bread, crust off 2 cups minced onion 4 ounces (1 stick) butter, plus 2 tablespoons or so soft butter 6 to 7 pound unblemished pumpkin 1 1/2 cups coarsely grated Swiss cheese 2 to 2 1/2 quarts chicken stock, brought to simmer Seasonings: salt, freshly ground pepper, 1/2 tsp. sage 1 cup heavy cream (or sour cream liquified with a little milk or stock), desirable but optional 1/2 cup lightly pressed chopped, fresh parsley Special equipment suggested: A lightly buttered pizza pan to hold pumpkin in oven and a long-handled ladle for serving.

Spread crumbs in roasting pan in 350 degree oven 15 minutes or so, tossing once or twice to dry out. They should barely color. Meanwhile, melt butter stick and slowly cook onions in it until translucent and tender - about 15 minutes. Toss crumbs with onions, stirring 3 minutes.

Cut a neat cover off pumpkin top, scrape out seeds and flesh. Rub inside and cover inside with soft butter. Place on pizza pan.

Turn crumb mixture into pumpkin, stir in grated cheese; fill pumpkin to within 2 inches of top with hot chicken stock. Season to taste.

Place pumpkin at once in lower level of preheated, 400 degree F. oven. Bake until pumpkin has just softened - but do not overcook, or it will collapse.

Just before serving, bring optional cream almost to the simmer; gently stir into soup, add parsley. Correct seasoning. At table, ladle soup into hot bowls, scraping off some of the flesh inside the pumpkin as you do so.

Note: You may keep it warm half an hour or so in a 175 degree F. oven until ready to serve. Too much heat and too long a wait will dangerously soften the pumpkin.

Serves 8 to 10.