Grease a 23cm (9 1/2 inch) springform pan, line base and side with foil, grease the foil. Beat the egg whites in bowl until soft peaks form, gradually add sugar, beating until dissolved between each addition. Chop almonds, fold through egg mixture. Fold in dates and chocolate. Be careful not to deflate the whites too much. Spread mixture into prepared pan, bake in at 170C/325F for about 40 minutes. Cool in pan. Place torte on a serving plate, carefully remove the foil, cover torte with lightly whipped heavy cream and decorate with some extra grated bittersweet chocolate. Refrigerate several hours before serving. Note: This torte is best served the day it is made.