Combine first 6 ingredients in a medium bowl, stirring well with a whisk.
Combine milks in a medium saucepan; bring to a simmer. Remove from heat; add bittersweet chocolate to pan, stirring until chocolate melts. Gradually stir about one-fourth of hot chocolate mixture into egg mixture; add egg mixture to remaining chocolate mixture in pan, stirring constantly. Cook over medium heat 5 minutes or until mixture is thick and creamy, stirring constantly. Pour into a bowl; cover surface of pudding with plastic wrap. Chill. Top with raspberries and white chocolate.