In medium saucepan (or you can use a double boiler), combine chocolate chips, coffee, 1/4 cup of the sugar, and 2 tablespoons of water. Stir constantly over low heat, until chocolate is melted and sugar is dissolved.
Remove from heat. using a wooden spoon, beat until smooth then let cool slightly.
Add the vanilla.
Beat in the egg yolks, one at a time, beating well after each addition.
In a medium bowl with an electric mixer, beat the egg whites just until soft peaks form when beater is slowly raised.
Add remaining sugar, 1 tablespoon at a time, beating well after each addition. Beat until stiff peaks form.
With rubber spatula or wire whisk, gently fold chocolate mixture into egg white mixture until combined well.
Spoon into six serving dishes and refrigerate until well chilled, about an hour, or until serving time. Garnish with whipped cream.