Anyone can make sensational chocolate desserts, as long as you remember to handle chocolate with care. Moisture and heat are chocolate's worst enemies.
Gentle heat is essential when you're melting chocolate--if overheated it may take on a burnt taste or a gritty texture. Set the bowl of chocolate above a pan of hot, not-quite-simmering water and stir it often. Because milk and white chocolates are even more sensitive to heat than dark chocolate, I melt them only partially above the hot water; they finish melting off the heat. You can also melt chocolate on medium power in the microwave, but check it frequently. Microwaved chocolate cubes don't appear melted to the eye, but as soon as you stir them, they liquefy.
Do not cover the chocolate. Steam condensing on the lid may drip into the chocolate and make the pieces stick together and seize, or harden. Seizing can also occur if you splash water into the chocolate or if you melt it with a tiny amount of liquid. To add flavorings, melt every 2 ounces of chocolate with at least 1 tablespoon of coffee, juice, liqueur, cream or milk, or with 1/4 cup of butter.
You can rescue seized chocolate by adding liquid by tablespoons or mild-flavored oil by teaspoons. This is likely to work but may throw off your recipe. Adding enough liquid to make sauce will salvage your chocolate, but for the dessert you're preparing you'll need a new batch.
Bittersweet and semisweet chocolates are usually interchangeable. You can use bars of fine dark eating chocolate, not just the kind in the market's baking aisle. Do not substitute unsweetened chocolate.
Faye Levy's "Chocolate Sensations" (HP Books, 1986) won the International Assn. of Culinary Professionals' best dessert book award.
Chocolate Mousse Three Ways
Active Work and Total Preparation Time: 30 minutes, plus 2 hours chilling
To turn this dark chocolate mousse into milk or white chocolate mousse, follow the variations below. Milk and white chocolate set less firmly than dark chocolate when chilled, so I add more butter. You can make the mousses up to 2 days ahead. For special occasions I layer all three mousses in a wine glass, beginning with the white mousse (the thinnest), followed by the milk chocolate, then the dark. I chill each layer about 1 1/2 hours and only then I prepare and add the next mousse.
12 ounces fine-quality bittersweet or semisweet chocolate, chopped
3/4 cup whipping cream
3 tablespoons unsalted butter, room temperature, cut in tablespoon-size pieces
6 eggs, separated, room temperature
1 tablespoon sugar
Choose a bowl that can sit snugly above a saucepan. Add enough water to the saucepan so it doesn't touch the bowl and heat it to nearly simmering. Combine the chocolate and the cream in the bowl. Set the bowl above the saucepan over low heat. Leave the chocolate just until melted, stirring occasionally with a dry wooden spoon. Remove the bowl; stir the chocolate until smooth.
Whisk in the butter. Add the egg yolks, one by one, whisking vigorously after each addition.
In a dry bowl, whip the egg whites with dry beaters at medium speed until soft peaks form. Beat in the sugar and whip at high speed until the whites are just stiff and shiny but not dry.
Quickly fold about a fourth of the whites into the chocolate mixture. Spoon this mixture over the remaining whites and fold them gently until blended in.
Divide the mixture among 6 small wine glasses, ramekins or small deep dessert dishes. Refrigerate the mousses for 2 hours or until they set. Serve cold.
6 servings. Each serving: 454 calories; 74 mg sodium; 243 mg cholesterol; 33 grams fat; 19 grams saturated fat; 39 grams carbohydrates; 9 grams protein; 3.34 grams fiber.
Milk Chocolate Mousse: Melt 12 ounces milk chocolate with the cream as above, leaving it above the hot water only until partially melted. Off the heat, whisk it until smooth. Whisk in 6 tablespoons butter. When beating the egg whites, add only 2 teaspoons sugar. Refrigerate until set before serving.
White Chocolate Mousse: Melt 12 ounces white chocolate with the cream as above, leaving it above the hot water only until partially melted. Off the heat, whisk it until smooth. Whisk in 9 tablespoons (1 stick plus 1 tablespoon) butter. When beating the egg whites, add only 1 1/2 teaspoons sugar. Refrigerate until set before serving.
Note: Although many recipes call for uncooked eggs, the U.S. Department of Agriculture has found them to be a potential carrier of food-borne illness and recommends that infants, the elderly and immuno-compromised people avoid raw eggs.