Passover Sponge Cake - cooking recipe

Ingredients

9 eggs (separate whites)
1 1/2 c. sugar
1/4 c. oil
juice of 1/2 orange and 1/2 lemon (1/4 c.)
1 full c. matzah cake meal and potato starch, combined
rind of lemon and orange (1 Tbsp.)

Preparation

Beat egg whites until frothy.
Add a pinch of salt.
Gradually add 1/2 cup sugar to whites.
Beat until glossy and peaks form. Beat egg yolks in another bowl.
Gradually add the oil, sugar and juice.
Beat well about 5 minutes or so until light in color and thick.
Add rind.