Chocolate Lemon Marble Chiffon Cake

Move other rack to lowest position. Heat oven to 325°F (160°C).

For Cake: In medium bowl, mix together cocoa and hot water; stir in 3 tablespoons sugar and 2 tablespoons oil; set aside.

In a large bowl, with wooden spoon stir together flour, remaining 1 1/2 cups sugar, baking powder and salt; add cold water, remaining 1/2 cup oil and egg yolks; beat with spoon until smooth.

In another large bowl, beat egg whites and cream of tartar on high speed of mixer until stiff peaks form. Pour egg yolk mixture in a thin stream over beaten whites, gently folding just until blended. Remove 2 cups batter; add to chocolate mixture, gently folding in until well blended.

Fold lemon peel into remaining batter.

Spoon half of lemon batter into ungreased 10-inch tube pan; drop half the chocolate batter on top by spoonfuls. Repeat layers of lemon and chocolate batters. Gently swirl with knife for marbled effect.

Bake 1 hour and 15 to 20 minutes or until top springs back when touched lightly. Immediately invert cake in pan onto heatproof funnel; cool completely. Remove cake from pan; invert onto serving plate.

For Lemon Glaze: In medium saucepan melt butter over low heat. Remove from heat; gradually whisk in powdered sugar, lemon juice and lemon peel, beating until smooth and of desired consistency. Spread over top of cake, allowing glaze to decoratively run down sides. Garnish as desired.