Marble Chiffon Cake - cooking recipe

Ingredients

2 1/4 cups sifted cake flour
1 1/2 cups sugar
3 teaspoons baking powder
1 teaspoon salt
1/2 cup salad oil
7 egg yolks
3/4 cup cold water
1 teaspoon vanilla
7 egg whites
1/2 teaspoon cream of tartar
1/4 cup boiling water
2 tablespoons sugar
2 ounces unsweetened chocolate squares

Preparation

Sift together the cake flour, 1 1/2 cups sugar, baking powder and salt.
Make a well in the center of dry ingredients and add in order: salad oil, egg yolks, cold water, and vanilla. Beat until satin smooth.
In a large bowl, beat egg whites and cream of tarter until very stiff peaks form. If there is a speck of grease or egg yolk, the whites won't whip up!
Pour egg yolk mixture in thin stream over entire surface of the egg whites, GENTLY folding to blend.
Remove 1/3 of the batter to a separate bowl.
Blend together the boiling water, 2 Tbsp sugar and unsweetened chocolate, melted; cool.
Gently fold chocolate mixture into 1/3 portion of batter.
Spoon half the light batter into UNGREASED 10 inch tube pan; top with half the chocolate batter. Repeat layers. With narrow spatula or butter knife, swirl gently through batters to marble. Leave definite areas of light and dark batters.
Bake in a 325 degree oven, about 65 minutes or till cake springs back when pressed lightly with finger.
Invert cake in pan and cool completely before removing from pan.