7 extra large egg whites
1 cup sugar
½ pounds unsalted butter, cut into small pieces
½ pound European bittersweet chocolate, broken into small pieces.
1 tablespoon pure vanilla extract
1 tablespoon espresso (or strong instant coffee, mixed with water and cooled)
3 tablespoons Kahlua
Preheat oven to 300ºF. Grease and flour a 10-inch spring form pan. Place egg whites and sugar in a mixing bowl and whip into firm peaks. Melt butter over medium heat and add chocolate, stirring till smooth. Quickly add vanilla, espresso/coffee, Kahlua and chocolate butter to egg whites and gently fold until smooth. Pour into prepared cake pan and bake on center rack for 40 minutes. Remove from oven. Wait 5 minutes and press sides down so the top of cake is even. Cool and refrigerate for 4 hours or until set. Remove cake from pan. Cut with hot knife into 8 pieces. Serve with berries or vanilla ice cream.
NOTE: This cake is extremely rich. Do not give overly generous portions. Whipped cream, faux whipped cream, ice cream or non-dairy frozen desserts cut some of the richness.