Orange Sponge Cake

Directions

1. 1
   Combine flour and 1/3 cup sugar; set aside.
2. 2
   Beat egg yolks until thick and lemon colored (about 3 to 5 minutes).
3. 3
   Add orange peel and juice; beat until very thick.
4. 4
   Gradually add 2/3 cup sugar and salt, beating constantly.
5. 5
   Sift flour mixture over egg yolk mixture a little at a time, folding just until blended.
6. 6
   Wash beaters.
7. 7
   Beat egg whites with cream of tartar until soft peaks form.
8. 8
   Gradually add 1/2 cup sugar, beating until stiff peaks form.
9. 9
   Thoroughly fold yolk mixture into whites.
10. 10
    Bake in ungreased 10-inch tube pan at 325° for about 55 minutes.
11. 11
    Invert cake in pan to cool.