ELEGANT CHOCOLATE MOUSSE CAKE

Steps:

• Mix chocolate wafer crumbs and butter together in a bowl. Press over the bottom and up the sides of a 10-inch springform pan. Freeze until firm, 20 to 30 minutes.
• Melt chocolate in top of a double boiler over simmering water, stirring frequently and scraping down the sides with a rubber spatula, about 5 minutes. Remove from heat.
• Whisk 2 eggs and 4 egg yolks in a bowl. Gradually pour in melted chocolate, whisking constantly, until well blended.
• Beat egg whites in a glass, metal, or ceramic bowl until stiff peaks form.
• Beat cream in a chilled glass or metal bowl with an electric mixer until foamy. Add 6 tablespoons confectioners' sugar; continue to beat until soft peaks form.
• Fold one-third of the egg whites and one-third of the whipped cream into the chocolate mixture until lightened. Fold in remaining egg whites and whipped cream until thoroughly incorporated. Pour into the crust.
• Chill cake until mousse is set, 6 hours to overnight.
• Combine 2 cups heavy cream, 1/4 confectioners' sugar, and orange liqueur in a large bowl; beat until stiff peaks form. Spoon into a pastry bag fitted with a star tip. Pipe whipped cream rosettes to garnish each slice.