1 Add instant coffee granules to hot coffee; mix well. 2 Add baking soda and set aside.3 Beat egg whites, adding cream of tartar while beating, until stiff. 4 Combine all ingredients except egg whites and mix until batter is smooth. Carefully fold in egg whites.5 Pour batter into ungreased angel food cake pan. Bake at 350°F for 1 hour or until cake tester inserted in center comes out clean or cake springs back when lightly touched on top. 6 Do not overbake. Invert pan onto neck of bottle. Cool thoroughly before removing cake from pan.