Chocolate Angel Food Cake with Chocolate Icing

Directions

1. Place egg whites in a large bowl; let stand at room temperature for 30 minutes. Sift flour and cocoa together twice; set aside.
2. Add the cream of tartar, extracts and salt to egg whites; beat on medium speed until soft peaks form. Gradually add sugar, about 2 tablespoons at a time, beating on high until stiff glossy peaks form and sugar is dissolved. Gradually fold in flour mixture, about 1/2 cup at a time.
3. Gently spoon into an ungreased 10-in. tube pan. Cut through batter with a knife to remove air pockets. Bake on the lowest oven rack at 350° for 30-40 minutes or until lightly browned and entire top appears dry. Immediately invert pan; cool completely, about 1 hour.
4. Run a knife around side and center tube of pan. Remove cake to a serving plate.
5. For icing, in a small bowl, beat the confectioners’ sugar, cocoa, sour cream, milk and vanilla until smooth. Drizzle over cake. Refrigerate leftovers.