Combine half-and-half, chocolate and sugar in small heavy saucepan. Whisk over medium heat for 10 minutes or until the mixture reaches a full boil and thickens.
Slowly stir about half of hot chocolate mixture into beaten egg yolks to temper the yolks. Re-introduce egg yolk mixture into remaining hot chocolate mixture. Cook and stir over low heat for 2 minutes. Remove from heat.
Stir in Frangelico and vanilla. Pour chocolate mixture into six ramekins or pots de crème cups. Cover and chill for at least 2 hours.
In a chilled bowl, beat cream with sugar and Frangelico until soft peaks form, using electric mixer at medium speed.
Garnish each pot de crème with whipped cream.