Preheat oven to 325 degrees F (165 degrees C). Have all ingredients at room temperature.
Melt the 5 ounces of the chocolate in a double boiler over hot water. Remove from heat and let cool.
Separate the eggs. Cream the butter and sugar together until light and fluffy. Beat the egg yolks in gradually until light in color. Add the melted, cooled chocolate and beat it in. Gradually add the sifted flour to the batter.
Beat the egg whites until stiff but not dry and fold them into the mixture. Pour batter into one ungreased 9 inch springform pan.
Bake at 325 degrees F (165 degrees C) for 50 to 60 minutes. Allow cake to cool completely before removing from pan and icing. Once cool remove from pan and slice cake horizontally. Set top half aside and spread filling of pureed jam between the layers. Cover top and sides with warm Sachertorte icing.
To Make Sachertorte Icing: Melt 1 tablespoon butter and 4 ounces chocolate in a double boiler over hot water. Add the coffee and beat well. Sift and add the confectioners sugar and 1 teaspoon vanilla. Spread the warm icing on the top and sides of the torte