Chocolate Mousse

6 ounces fine semi-sweet chocolate
2 tablespoons butter
1/2 cup cream
6 egg yolks
1/4 cup coffee liqueur
4 egg whites
  1. Melt chocolate with butter in a double boiler over steaming water; don't allow even a drop of water to get in the chocolate. While chocolate and butter are melting, meanwhile, whip cream until stiff.
  2. Stir chocolate and butter until smooth and shiny. Beat in the egg yolks, one at a time. Add coffee liqueur and stir. Slowly fold in the whipped cream. Refrigerate 30 minutes (while keeping the egg whites at room temperature).
  3. Whip egg whites to stiff peak stage. Fold this into the mousse. Portion into four serving cups (wine glasses are nice) and cover with saran wrap; refrigerate several hours or overnight. Serve with a dollop of whipped cream sprinkled with shaved chocolate.