Preheat oven to 350 degrees. Grease a set of three 9 by 1 inch checkerboard cake pans, line with parchment, and then grease and flour, again.

In a double boiler melt the chocolate over simmering water, stirring frequently. Remove from heat.

In a medium bowl lightly combine the eggs (and egg whites), 1/4 of the milk, and vanilla.

In bowl of electric mixer, combine the dry ingredients and mix on low speed for 30 seconds to blend. Add the shortening (or butter) and remaining milk. Mix on low speed until the dry ingredients are moistened.  Increase to medium speed and beat for 1 1/2 minutes to aerate and develop the cake's structure. Scrape down the sides. Gradually add the egg mixture in three batches, beating for 20 seconds after each addition to incorporate the ingredients and strengthen the structure.  Scrape down the sides.

Divide the batter approximately in half. Stir the melted chocolate into the smaller batch of batter until uniform in color. Fill 2 large pastry bags fitted with large round tubes 3/4 inches in diameter with the 2 batters.

Place the divider rings in one of the prepared pans and pipe batter into each, alternating batter colors (for example - outer and inner ring yellow, middle ring chocolate). The batter should fill the pan about half full. Using a small metal spatula or the back of a spoon, smooth any seams or divisions in the batter. Now carefully lift out the divider and rinse it off. When piping batter for the second layer, alternate the colors, i.e. if you started with yellow for the outside ring, start with the chocolate. Pipe batter for the third layer exactly like the first.

Bake 20 - 25 minutes or until a tester inserted near the center comes out clean and the cakes spring back when pressed lightly in the centers. The cakes should start to shrink from the sides of the pans only after removal from the oven.

Let the cakes cool in the pans on racks for 10 minutes. Loosen the sides with a small metal spatula and invert onto greased wire racks. To prevent splitting, reinvert so that the tops are up and cool completely before wrapping airtight. Trim layers so they are flat.

Line up layers so on the outside, the chocolate and vanilla sections alternate. When stacking the layers, use a very thin coating of chocolate ganache to adhere the layers for a better checkerboard effect. Frost with Chocolate Fudge Icing. 

Store 2 days at room temperature or 5 days refrigerated. Texture is best the same day as baking. 

Adapted from Cake Bible by Rose Levy Beranbaum

MOIST CHECKERBOARD CAKE RECIPE: Serves 16. Any time you see buttermilk or sour cream in a recipe instead of milk, it will be moist

Grease and flour three 8 x 1 1/2-inch round baking pans. Preheat oven to 350 degrees F.

In a bowl combine flour, baking powder, soda, and 1/2 teaspoon salt. 

In a very large bowl beat shortening with an electric mixer on medium speed for 30 seconds. Add 1 2/3 cups of sugar and vanilla; beat till combined. Alternately add flour mixture and buttermilk, beating after each addition just till combined. 

Thoroughly wash beaters. Beat egg whites on medium until soft peaks form (tips curl). Gradually add remaining sugar, beating on medium to high till stiff peaks form (tips stand straight). Gently fold half on the egg white mixture into beaten mixture. Fold in the remaining egg white mixture. 

Spoon half of the batter (about 3 1/4 cups) into a bowl. Sift cocoa powder over remaining batter. Stir in the 1 tablespoon milk. Set 3/4 cup of white batter aside. 

Spoon 1 1/4 cups of remaining white batter around the outer edge of each of two of the prepared pans. Spoon 3/4 cup of chocolate batter in a ring right next to the outer edge of white batter in each of the pans. Spoon half of the remaining white batter in the center of each pan. 

In the third pan, using 1 1/4 cups of chocolate batter, make an outer ring. Using the reserved 3/4 cup white batter, make inner ring. Fill center with the remaining chocolate batter. 

Bake at 350 F degrees about 25 minutes or till cakes test done. Cool in pans about 10 minutes. Remove and cool. 

Place a cake layer with a white outer ring on serving plate. Frost top with 1/2 cup frosting. Place cake layer with chocolate outer ring on top. Frost top with 1/2 cup frosting. Top with remaining layer. Frost sides and top with remaining frosting. 

Chocolate Frosting  Makes 4 cups.

Beat together 1/4 cup margarine and 2 cups sifted powdered sugar. Beat in 3 squares (3 ounces) unsweetened chocolate, melted and cooled; 1/2 cup milk; and 1 teaspoon vanilla. Beat in 2 1/2 to 3 cups sifted powdered sugar to reach desired consistency. 

EASY CHECKERBOARD CAKE RECIPE
1 box of yellow Duncan Hines (or other brand) cake mix
1 box of chocolate Duncan Hines (or other brand) cake mix