1. In a three-quart saucepan, heat whip cream until begins to boil. Remove from heat.
2. Divide among three bowls as follows:
Bowl #1: 1 and 1/4 cups cream and semisweet chocolate
Bowl #2: 1/2 cup cream and milk chocolate
Bowl #3: 1/2 cup cream and white chocolate with extract
3. Mix contents of each bowl until well combined. Refrigerate all three bowls for three hours.
4. Beat semisweet chocolate until peaks form. Divide among 12-and-1/2-ounce trifle cups. Refrigerate for 10 minutes.
5. Beat milk chocolate mixture until peaks form. Spread over bittersweet chocolate layer. Refrigerate.
6. Garnish with chocolate curls or chopped Viennese crunch.
7. Repeat with white chocolate.