Melt chocolate with coffee in the microwave very slowly so as not to scorch. Remove from microwave and stir until smooth. Beat the butter into the chocolate and add the egg yolks one by one and mix thoroughly. Let the chocolate mixture cool. Beat the heavy cream until thick. Beat egg whites and add the sugar in a sprinkling fashion until the whites form stiff peaks. Fold the chocolate, whipped cream and the egg whites together gently. Turn the mousse into a serving bowl or individual serving dishes. Chill several hours. Serves 6 to 8.
From the Cookbook, "Blueberry Peaches, Red Robin Pie" by Stella and Paul La Violette