1. Heat oven to 325°F.
2. Combine 1-3/4 cups sugar, flour, cocoa, baking powder, salt and baking soda in large bowl. Add oil, egg yolks, water and vanilla; beat until smooth.
3. Beat egg whites and cream of tartar in extra-large bowl until soft peaks form. Gradually add remaining 1/4 cup sugar, beating until stiff peaks form. Gradually pour chocolate batter over beaten egg whites, folding with rubber spatula just until blended. Pour into ungreased 10-inch tube pan.
4. Bake 1 hour and 20 minutes or until top springs back when touched lightly. Invert pan on heat-proof funnel until completely cool. Remove cake from pan; invert onto serving plate. Spread top of cake with VANILLA GLAZE, allowing some to drizzle down sides. Makes 12 servings.
1/3 cup butter or margarine
2 cups powdered sugar
1-1/2 teaspoons vanilla extract
2 to 4 tablespoons hot water
Melt butter in medium saucepan over low heat. Remove from heat. Stir in powdered sugar and vanilla. Stir in water, 1 tablespoon at a time, until smooth and of desired consistency. About 1-1/4 cups glaze.
VARIATION: COCOA PEPPERMINT CHIFFON CAKE: Omit vanilla extract; add 1 to 1-1/2 teaspoons peppermint extract. Add red food color to VANILLA GLAZE for pink colored glaze. Garnish with crushed hard peppermint candy.