Method:

• Heat oven to 350°F (180°C) for shiny metal or glass pans or 325°F (160°C) for dark or non-stick pans. Grease bottoms and sides of three 9-inch (23 cm) round baking pans of checkerboard cake set with shortening; lightly flour.
• Place divider ring in one of the pans, following manufacturer's directions.
• In medium bowl, beat cake mix, milk, cream cheese, vanilla and eggs with electric mixer on low speed 1 minute, scraping bowl constantly. Beat 2 minutes longer. Divide batter in half; stir cocoa into half of batter.
• Spoon batter into pan with divider ring, following manufacturer's directions. Repeat for each cake layer.
• Bake 35 to 40 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes; loosen side of cake from pans with metal spatula; turn upside down onto cooling rack. Remove pans. Cool completely, about 1 hour.
• Using a thin layer of frosting between layers, stack cake layers so outside colors of cake alternate. Place cake on serving plate; frost side and top of cake with frosting.