Sweet dessert souffles-who can resist them? Rich yet light, they are a perfect ending for any meal. Almost every French restaurant habitue has marveled as a fluted white souffle dish is carried through the dining room with that fickle mixture of stiffly beaten egg whites, cooked butter and flour magically rising straight up like a golden toque.

Yet every classic theme, whether in music or food, has its variations and souffles are no different.

Austria is the home of the Salzberger Nockerl or Salzburg style omelette souffle. This provincial specialty consists of several marbled yellow and white mounds liberally dusted with confectioners' sugar.Served hot on an oval silver platter, this souffle is very fluffy, bakes very quickly and should be served when guests are asking for coffee refills.

Another variation is the old-fashioned souffled pudding. This souffle has a cake-like texture and is not as temperamental as the omelette souffle.It needn't be served immediately. Souffled puddings are generally poached in a simmering bain-marie or waterbath and made in individual timbales or custard cups.

Although there are several other variations, souffles for the most part fall into two main categories. Cream-based souffles such as the typical restaurant souffle Grand Marnier starts with a base of pastry cream. Fruit-based souffles are made from pureed fresh or dried fruits. All souffles can be garnished with a dusting of confectioners' sugar or served with a sauce, such as creme anglaise or chocolate sauce.

Souffles in general are not as tempermental as commonly depicted but the sequence of mixing ingredients is quite crucial to a successful outcome. Also souffles are always cooked in a moderately hot (400 to 450 degree) oven, so that the heat may reach the center of the souffle gradually.

Here are two excellent souffle recipes by Chef Bruno Ellmer and Fritz Sonnenschmidt, both chef-instructors at The Culinary Institute of America and members of the 1976 U. S. Culinary Olympic team.

CHEF ELLMER'S SALZBERGER NOCKERL

(2 or 3 servings) 4 egg whites 4 tablespoons sifted confectioners' sugar 1 tablespoon unsifted all-purpose flour 1/4 teaspoon grated lemon rind (optional) 1 teaspoon vanilla sugar or extract 3 egg yolks, beaten 1 tablespoon sweet butter Milk Confectioners' sugar

In a large bowl, beat egg whites by hand or with an electric mixer until stiff. Add sifted confectioners' sugar, 1 teaspoon at a time, until the egg whites reach the consistency of a heavy meringue or when most of the egg-white mixture can be lifted up with the whip or beaters.

Sift flour over egg whites and fold in together with lemon rind and vanilla sugar or extract. Then fold in beaten egg yolks. Mix lightly and gently with a rubber scraper, leaving prominent yellow and white streaks. Do not use a wire ship. It will mix the ingredients too well and deflate the meringue.

Combine butter and enough milk to barely cover the bottom of a shallow, fireproof dish and cook lightly on the top of the stove until thick and the dish is heated.

Using the rubber scraper, place 2 or 3 heaping mounds of egg white mixture diagonally across the dish. Bake in a preheated 450-degree oven for 5 to 7 minutes, or until the top is just brown.

Dust with confectioners' sugar and serve quickly. Omelette souffle will not rise during baking because of the stiff meringue.

CHEF SONNENSCHMIDT'S CHOCOLATE SOUFFLED PUDDING

(8 servings) 5 tablespoon sweet butter 1/3 cup confectioners' sugar 4 egg yolks, beaten 2 1/2 ounces semi-sweet chocolate, melted 1/2 cup almonds 1/2 cup breadcrumbs, finely grated 4 egg whites 1/4 cup granulated sugar

Cream together butter and confectioners' sugar. Add and beat in egg yolks. Add melted chocolate gradually and continue to beat. Grate almonds to a fine texture and add to chocolate mixture. Then add breadcrumbs and mix.

In a separate bowl, beat whites until stiff. Gradually beat in granulated sugar. Carefully fold egg whites into the chocolate mixture with a rubber scrapter.

Butter and floud 8 timbales or custard dishes. Fill each mold halfway. (Souffled puddings will rise slightly.) Set molds in a bain-marie of slight simmering water. The water should cover the bottom third of the mold. Cover bain marie loosely with a sheet of aluminum foil with holes in it to allow excess steam to escape. Cook the pudding at a slow simmer in the waterbath for 15 to 20 minutes, or until the pudding feels firm to the touch and pulls away slightly from the edges. CAPTION: Illustration, no caption