Passover chocolate sponge cake

MMMMM----- Recipe via Meal-Master (tm) v8.01
  
       Title: Passover Chocolate Sponge Cake
  Categories: Cakes, Chocolate
       Yield: 6 servings
  
      12    Eggs, separated
   1 1/2 c  Sugar
       2 tb Cold water
            Juice and grated rind of 1
            -orange
     1/2 lb Sweet chocolate, grated
     3/4 c  Matzo cake flour
  
   Preheat oven to 350^F.
   
   Beat egg yolks and sugar until light and fluffy (about 7 minutes).
   Add cold water, orange juice, orange rind, chocolate and cake flour.
   Gently fold in stiffly beaten egg whites.
   
   Pour into a 10-inch tube pan with removable insert.  Bake for 55 to 65
   minutes or until cake springs back when gently pressed. Cool
   completely, inverted on cake rack, before removing from pan.
  
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