Anne Byrn is the author of the bestselling Cake Mix Doctor series and The Dinner Doctor, with over 3.5 million copies in print. She makes frequent appearances on Good Morning America and QVC. She lives in Nashville, Tennessee, with her family. Her website is www.cakemixdoctor.com.

SERVES: 16

PREPARATION TIME: 10 MINUTES

BAKING TIME: 28 TO 32 MINUTES

ASSEMBLY TIME: 10 MINUTES

Solid vegetable shortening for greasing the pans

Flour for dusting the pans

1 package (18.25 ounces) devil's food cake mix with pudding

1 cup sour cream

3/4 cup water

1/2 cup vegetable oil

3 large eggs

1 teaspoon pure vanilla extract

Chocolate Sour Cream Frosting (see below)

1. Place a rack in the center of the oven and preheat the oven to 350ªF. Generously grease two 9-inch round cake pans with solid vegetable shortening, then dust with flour. Shake out the excess flour. Set the pans aside.

2. Place the cake mix, sour cream, water, oil, eggs, and vanilla in a large mixing bowl. Blend with an electric mixer on low speed for 1 minute. Stop the machine and scrape down the sides of the bowl with a rubber spatula. Increase the mixer speed to medium and beat 2 minutes more, scraping down the sides again if needed. The batter should look well combined. Divide the batter between the prepared pans, smoothing it out with the rubber spatula. Place the pans in the oven side by side.

3. Bake the cakes until they spring back when lightly pressed with your finger, 28 to 32 minutes. Remove the pans from the oven and place them on wire racks to cool for 10 minutes. Run a dinner knife around the edge of each layer and invert each onto a rack, then invert again onto another rack so that the cakes are right side up. Allow to cool completely, 30 minutes more.

4. Meanwhile, prepare the Chocolate Sour Cream Frosting.

5. Place one cake layer, right side up, on a serving platter. Spread the top with frosting. Place the second layer, right side up, on top of the first layer and frost the top and sides of the cake with clean, smooth strokes.

• The Cake Mix Doctor says: If you are trying to cut calories and fat, substitute plain yogurt for the sour cream in the cake batter. But be forewarned that the sour cream produces a far moister cake than one with yogurt.

  Chocolate Sour Cream Frosting

  MAKES 3 CUPS, ENOUGH TO FROST A 2- OR 3-LAYER CAKE OR 30 CUPCAKES

  PREPARATION TIME: 10 MINUTES

  8 tablespoons (1 stick) butter, cut into 8 pieces

  2/3 cup unsweetened cocoa powder

  3 cups confectioners' sugar, sifted

  1/3 cup sour cream

  1 teaspoon pure vanilla extract

  1. Melt the butter in a small saucepan over low heat or melt it in a large glass bowl in the microwave oven on high power for 45 seconds.

  2. Place the melted butter in a large mixing bowl and add the cocoa powder. Whisk until smooth. Add the confectioners' sugar alternately with the sour cream, blending with an electric mixer on low speed for 1 to 11/2 minutes, or until incorporated. Stop the machine and add the vanilla. Increase the mixer speed to medium and beat until light and fluffy, 1 minute more.

  3. Use the frosting to frost the top and sides of the cake or cupcakes of your choice.

  Store this cake in a cake saver or under a glass dome, in the refrigerator for up to 1 week. Or freeze it, in a cake saver, for up to 6 months. Thaw the cake overnight in the refrigerator before serving.

  Amazing German Chocolate Cake/

  SERVES: 16

  PREPARATION TIME: 8 MINUTES

  BAKING TIME: 48 TO 52 MINUTES

  Vegetable oil spray for misting the pan

  Flour for dusting the pan

  1 package (18.25 ounces) plain German chocolate cake mix

  1 container (15 ounces) coconut pecan frosting

  1 cup water

  1/3 cup vegetable oil

  3 large eggs

  1. Place a rack in the center of the oven and preheat the oven to 350ªF. Lightly mist a 12-cup Bundt pan with vegetable oil spray, then dust with flour. Shake out the excess flour. Set the pan aside.

  2. Place the cake mix, frosting, water, oil, and eggs in a large mixing bowl. Blend with an electric mixer on low speed for 1 minute. Stop the machine and scrape down the sides of the bowl with a rubber spatula. Increase the mixer speed to medium and beat 2 minutes more, scraping the sides down again if needed. The batter should look thick and well combined. Pour the batter into the prepared pan, smoothing it out with the rubber spatula. Place the pan in the oven.

  3. Bake the cake until it springs back when lightly pressed with your finger, 48 to 52 minutes. Remove the pan from the oven and place it on a wire rack to cool for 20 minutes. Run a long, sharp knife around the edge of the cake and invert it onto a rack to cool completely, 20 minutes more.

  4. Slide the cake onto a serving platter and slice.

  • Store this cake, wrapped in plastic wrap or aluminum foil, or in a cake saver or under a glass dome, at room temperature for up to 1 week. Or freeze it, wrapped in foil, for up to 6 months. Thaw the cake overnight in the refrigerator before serving.

    White Chocolate Banana-Macadamia Cheesecake

    SERVES: 20

    PREPARATION TIME: 15 MINUTES

    BAKING TIME: 45 TO 50 MINUTES

    Softened butter for greasing the pan

    1 package (18.25 ounces) plain white cake mix

    1/2 cup finely chopped macadamia nuts

    4 tablespoons (1/2 stick) butter, melted

    4 large eggs, at room temperature

    6 ounces white chocolate, chopped

    2 packages (8 ounces each) cream cheese, at room temperature

    1 can (14 ounces) sweetened condensed milk

    2 small ripe bananas, peeled and mashed (about 3/4 cup)

    1/2 teaspoon pure vanilla extract

    1. Place a rack in the center of the oven and preheat the oven to 325ªF. Lightly grease a 13- by 9-inch pan with softened butter. Set the pan aside.

    2. Measure out 1/2 cup of the cake mix and set it aside for the filling.

    3. Place the remaining cake mix, the macadamias, the melted butter, and 1 egg in a large mixing bowl. Blend with an electric mixer on low speed for 2 minutes. Stop the machine and scrape down the sides of the bowl with a rubber spatula. The batter should come together into a ball. With your fingertips, pat the batter evenly over the bottom and 1 inch up the sides of the prepared pan, spreading it out with your fingers until smooth. Set the pan aside.

    4. Place the white chocolate in a small glass bowl and heat in the microwave oven on high power for 1 minute. Remove the bowl from the oven and stir with a small rubber spatula until it is melted. (See Melting White Chocolate, page 92.) Let it cool slightly.

    5. Place the melted white chocolate, cream cheese, and sweetened condensed milk in the same mixing bowl that was used for the crust. With the same beaters (no need to clean them either), blend with an electric mixer on low speed until just combined, 30 seconds. Stop the machine and add the reserved cake mix, the remaining 3 eggs, the mashed bananas, and the vanilla. Beat on medium speed for 1 minute. Stop the machine and scrape down the sides of the bowl with the rubber spatula. Pour the filling onto the crust, and spread it out with the rubber spatula so that it covers the entire surface and reaches the sides of the pan. Place the pan in the oven.

    6. Bake the cheesecake until it looks shiny and golden brown and the center no longer jiggles when you shake the pan, 45 to 50 minutes. Remove the pan from the oven and place it on a wire rack to cool for 30 minutes. Lightly cover the pan with plastic wrap and place it in the refrigerator to chill for at least 1 hour, or preferably 24 hours, for the flavors to meld. Cut into squares and serve.

    • Store this cake, covered first in plastic wrap and then in aluminum foil, in the refrigerator for up to 1 week. Or freeze it, wrapped in foil, for up to 2 months. Thaw the cake overnight in the refrigerator before serving.