Place the chocolate and butter in a small saucepan over low heat and stir until melted and smooth. Stir through the egg yolks and set aside. Whisk the eggwhites until soft peaks form. Gradually add the sugar and beat until stiff peaks form. Fold through the chocolate mixture, then the cream. Spoon into serving glasses and refrigerate until set. Top with the raspberries to serve. Serves 2.