Ingredients:

  Amount  Measure       Ingredient -- Preparation Method
--------  ------------  --------------------------------
   8      large         egg whites
   1      teaspoon      cream of tartar
   2      teaspoons     vanilla
   1      cup           sugar
   1      cup           cake flour
   1      tablespoon    orange zest -- minced
   1      tablespoon    lemon zest -- minced

Preparation:

Preheat oven to 325F. Grease a 10 inch tube pan. In a large bowl, beat the egg whites until foamy. Add the cream of tartar and vanilla and bean until soft peaks form. Continue beating while gradually adding the sugar, until peaks are firm but not stiff. Combine flour with orange and lemon zests. Carefully fold the flour into the egg whites. Spoon mixture into pan. Bake for 45 minutes.