Preheat oven to 350 degrees Fahrenheit.

In a bowl add sugar, cake meal, potato starch, cocoa, salt, and baking powder.

In an electric mixer or using a hand mixer, mix until well blended.

Make a well in the chocolate chiffon mixture and add oil, egg yolks, water, and vanilla. Mix for two minutes on medium speed.

In a separate bowl beat egg whites until soft peaks are formed. Then fold egg whites into batter gently.

Pour batter into ungreased nine-inch tube pan and bake at 350 degrees Fahrenheit for one hour and 10 minutes.

Remove cake from oven and invert pan on a heat resistant bottle until cool. Remove from pan after cake has cooled.