Chocolate-orange angel food cake

---------- Recipe via Meal-Master (tm) v8.05
  
       Title: Chocolate-Orange Angel Food Cake
  Categories: Cakes, Chocolate
       Yield: 16 servings
  
   1 1/2 c  Powdered sugar
     3/4 c  Cake flour
     1/4 c  Cocoa
   1 1/2 c  Egg whites; about 12
         ts Cream of tartar
       1 c  Granulated sugar
     1/4 ts Salt
       3 c  Orange sherbet; softened
  
   Recipe by: Betty Crocker's Low-Fat Cookbook
   Move oven rack to lowest position. Heat oven to 375 degrees.
   Sift together powdered sugar, flour, and cocoa. Beat egg
   whites and cream of tartar in large bowl on medium speed
   until foamy. Beat in granulated sugar, 2 Tbsp. at a time,
   on high speed, adding salt with the last addition of sugar.
    Continue beating until stiff and glossy. Do not underbeat.
   Sprinkle cocoa mixture, 1 tb at a time, over meringue,
   folding in just until cocoa mixture disappears. Spread
   batter in ungreased tube pan, 10x4 inches. Gently cut
   through batter with metal spatula.
   Bake 30 to 35 minutes or until cracks feel dry and top
   springs back when touched lightly. Invert pan onto metal
   funnel or glass bottle about 2 hours or until cake is
   completely cool. Remove from pan.
   
   Slice off top of cake about 1 inch down; set aside. Cut
   down into cake 1 inch from outer edge and 1 inch from edge
   of hole, leaving substantial "walls" on each side. Remove
   cake within cuts with curved knife or spoon, being careful
   to leave a base of cake 1 inch thick. Spoon sherbet into
   cake cavity; smooth top. Replace top of cake. Cover and
   freeze about 3 hours or until firm.  16 servings.
  
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