Dark Chocolate Mousse

1. Beat egg yolks in a small bowl with an electric mixer on high speed for about 3 minutes or until thick and lemon colored. Gradually beat in sugar.
2. Heat 1 cup whipping cream in a 2-quart saucepan over medium heat until hot. Gradually stir at least half of the hot whipping cream into the egg yolk mixture; stir this mixture back into the hot cream in the saucepan. Cook over low heat for about 5 minutes, stirring constantly, until the mixture thickens (do not boil).
3. Stir in the chopped dark chocolate until completely melted. Cover and refrigerate for about 2 hours, stirring occasionally, just until chilled.
4. Beat the remaining 1 1/2 cups whipping cream in a chilled medium bowl with an electric mixer on high speed until stiff peaks form.
5. Gently fold the whipped cream into the chilled chocolate mixture. Pipe or spoon the mousse into serving bowls. Refrigerate until serving. Optional toppings include raspberries and sprinkles.