Maida's desserts: from light and airy to dense and delicious

There was a certain chocolate cake that Maida Heatter, the ''queen of desserts,'' tasted at a restaurant in New York for which she decided she just had to have the recipe. But the restaurant wouldn't give it to her, so Maida began experimenting in her own kitchen in Miami Beach.

After 40 years of testing, sending pieces of the cake to every great pastry chef to analyze, and writing to food magazines, which seem to be able to get every recipe imaginable, Maida finally succeeded in re-creating the cake to her complete satisfaction.

This is the first recipe in her new book, ''Maida Heatter's New Book of Great Desserts'' (Knopf, $17.50). Those who have made the cake say it is all that the author has described it to be - moist, smooth, rich, dense, dark, and delicious.

But many of the other recipes in this new collection are light, airy, and fruity, and all are written in Maida's clear, thorough style. Her informal introductions to each recipe give her books a personal touch, and make them fun to read.

Maida told me she is particularly happy with the chapters on fruit desserts and ice creams. There are lots of imaginative recipes for fresh summer strawberries, and a hot peach and blueberry casserole with an old-fashioned crunchy topping.

Ice cream flavors range from Palm Beach Orange to Blueberry that is a deep red-purple color, one of the most beautiful colors Maida has ever seen in food. With the abundance of fresh fruits available now, this book will give you lots of ideas for summer desserts.

Maida cannot explain the seeming contradiction in this country between the emphasis on fitness and slenderness and the record sales of ice cream, as well as her books on desserts, cookies, and chocolate. But she believes that everyone likes desserts and enjoys making them for guests, and that guests appreciate a small slice of a special cake or pie, or a scoop of a homemade ice cream or sorbet, all of which add an elegant finishing touch to a dinner party.

Maida and her husband and recipe critique, Ralph Daniels, frequently travel and they find this a constant source of new recipes and ideas. Maida often shares her recipes in return. Once while in Rancho Sante Fe, Calif., she and her husband noticed a sign announcing the opening of a new bakery. She went in to investigate and ended up offering them her bran muffin recipe, which they now make every morning.

Here is one of Maida's desserts to make for a special occasion this summer. Make it at least 4 hours ahead or the day before. It is prepared in individual glasses that should have at least a 10-ounce capacity, although they can be larger if you wish.

This is food for angels; it is like eating a sweet, lemon-flavored cloud, like a glass of delicious nothingness.m

Lemon Mousse 1 envelope unflavored gelatin 2 tablespoons cold water Finely grated rind of 2 large lemons 1/2 cup plus 1 tablespoon fresh lemon juice 1 cup granulated sugar 1 cup egg whites, about 8 whites 1/8 teaspoon salt 1/8 teaspoon cream of tartar 1 cup heavy cream

Sprinkle gelatin over water in small cup and let stand for a few minutes. Meanwhile, place rind, juice, and 3/4 cup sugar in small saucepan and stir with wooden spatula until sugar is dissolved and mixture just comes to a boil.

Add softened gelatin, stir to melt, remove from heat, and pour mixture into large mixing bowl, preferably metal.

Partly fill a larger bowl with ice and water and place bowl of lemon mixture in it; stir constantly until mixture is cool to inside of wrist, but does not thicken. Remove bowl from ice water temporarily, reserve ice water, and set aside.

Place whites in large electric mixer bowl. Add salt and cream of tartar and beat until whites hold soft shape. Reduce speed to moderate and gradually add reserved 1/4 cup sugar. Then, on high speed, beat only until whites barely hold a definite shape; they should not be stiff or dry. Set aside.

In small, chilled bowl with chilled beaters, whip cream until it just barely holds a definite shape; it should not be stiff of dry. Set aside.

Replace bowl with lemon mixture in ice water and scrape bowl constantly with rubber spatula until mixture thickens to syrupy consistency.

Remove from ice immediately before it really stiffens and quickly fold about 1/4 of it into whipped cream. Then fold into second quarter. Then a third. With large rubber spatula, briefly fold cream and remaining lemon mixture together.

Lightly fold about a cup of beaten whites into cream, then another cupful. Finally fold cream and remaining whites only until barely blended.

Spoon mixture into 8 large glasses. Cover with plastic wrap without touching mousse. Refrigerate 4 hours or overnight.