Chocolate Chip Cookie Dough Cake

My oldest daughter discovered this cake years ago and it quickly became her favorite. She requests it for any occasion. Over the years we have tried different kinds of cake, different frostings, and even modifications to the cookie dough filling to improve it. This is our best and favorite version of this cake. Despite being filled with cookie dough, it is not overly sweet, partly because of the whipped frosting. This cake is even little sister approved.

For the cake:

• 2 cups sugar
• 3 cups flour
• 2 teaspoons baking soda
• 1 teaspoon salt
• 1 cup milk
• 1 tablespoon vinegar
• 2/3 cup oil
• 1 cup water

For the cookie dough:

• 1 cup butter, softened
• ½ cup sugar
• 1 cup brown sugar
• ¼ cup milk
• 2 ½ cups flour
• 1 teaspoon salt
• 1 cup mini chocolate chips

For the frosting:

• ¼ cup flour
• 1 cup milk
• 1 cup butter, softened
• 1 cup sugar

Additional tools:

• Mixing bowls
• Measuring cups, spoons
• Mixer, stand or hand
• Sifter or sieve (optional)
• 3 (9- or 10-inch) cake pans
• Vegetable oil spray
• Small Saucepan
• Mixing spoons, spatulas, whisk
• Knife for trimming
• Knife or spatula for frosting cake

For the cookie dough filling you will need the following ingredients:

• 1 cup butter, softened
• ½ cup sugar
• 1 cup brown sugar
• ¼ cup milk
• 2 ½ cups flour
• 1 teaspoon salt
• 1 cup mini chocolate chips

Start by lining a 9 inch cake pan with plastic wrap, overhanging the edges of the pan. The overhanging plastic wrap will be used to cover the cookie dough layer while it is being refrigerated.

I am using a stand mixer but a hand mixer will work as well. You can even do this by hand but it takes longer. In the bowl of a stand mixer (or a large mixing bowl), add the softened butter, sugar and brown sugar. Beginning on low and increasing to medium speed, cream the butter and sugars until light and fluffy using the paddle attachment. The butter/sugar mixture will become lighter in color. Scrape down the bowl to make sure all of the butter and sugar are combined before continuing to the next step.

Now that the the butter and sugar is light and fluffy, add flour and salt to the butter mixture. Starting on low speed, mix together the flour with the butter mixture. You can increase the speed of the mixer as the flour gets incorporated.

When the flour is almost all mixed in, scrape down the bowl again. Then add the milk and beat until the dough is well combined.

Add the chocolate chips and let the mixer run on medium for about 30 seconds to evenly distribute them throughout the dough. You could fold in the chocolate chips by hand but I prefer to use the mixer for this step as well.

Dump all of the cookie dough into the plastic wrap-lined cake pan.

Using a rubber spatula, press the cookie dough into the pan as evenly as possible. Press firmly so that it fills all the edges of the cake pan and doesn't leave any spaces. Also make the layer as level as you can.

Pull the overhanging edges of the plastic wrap over the cookie dough and cover completely. If needed, place another layer of plastic wrap over the top to make sure the entire layer is covered with plastic wrap or place the layer, cake pan included, into a Ziploc bag. Refrigerate until firm.

While the cookie dough layer is refrigerating, bake your cake.

For Cake you will need:

• 2 cups sugar
• 3 cups flour
• 2 teaspoons baking soda
• 1 teaspoon salt
• 1 cup milk
• 1 tablespoon vinegar
• 2/3 cup oil
• 1 cup water

Start by gathering all of your ingredients for the cake.

Preheat the oven to 350 degrees. Grease 2 9-inch baking pans with vegetable oil spray.

In a large bowl, combine sugar, flour, baking soda and salt. I sifted the flour, baking soda and salt into the sugar but this isn't necessary. I just prefer to use my sifter when I combine flour and baking soda in the same recipe to prevent any clumps of baking soda from being in the batter. I also prefer sifting flour in my cake recipes. Using the whisk attachment on the mixer, stir the dry ingredients together.

In a glass, combine milk and vinegar and let sit until ready to use. Measure out the water and the oil into separate glasses.

With the mixer running, add milk mixture, oil and half of the water to the dry ingredients. Mix until well combined and smooth. Scrape down the mixing bowl to make sure all ingredients are mixed in.

Then add remaining water and continue to mix until batter is smooth again and water is fully incorporated.

Pour cake batter evenly into greased baking pans.

Bake for about 30 minutes, until cakes are set, rotating the pans in the oven halfway through baking. Cakes are done when set to the touch and a toothpick inserted in the center comes out clean.

Cool the cakes in the pans on wire racks for 20-30 minutes. Then remove the cakes from the pans and cool completely on wire racks.

Once the cakes are baking, start your frosting. It will need time to cool as well before you can finish the frosting. You will need:

• ¼ cup flour
• 1 cup milk
• 1 cup butter, softened
• 1 cup sugar

Make sure your butter is out and softening before you start making the frosting. The frosting doesn't take very long to put together. It just takes time to cool in between the steps.

In a small saucepan, whisk flour and milk together until smooth. Then cook the flour/milk mixture over medium-high heat, stirring constantly, until the mixture is thick, about 3 to 4 minutes. When it is done, the mixture will be thick like pudding.

Transfer to a heatproof bowl. Cover the surface of the mixture with plastic wrap and let it cool to room temperature. Covering the surface with plastic wrap will prevent a "skin" from forming on the top of the mixture.

In a mixing bowl, beat butter and sugar with a paddle attachment until light and fluffy, about 2 minutes. The butter will be pale when it is ready. Scrape down the bowl to make sure all of the butter and sugar is mixed together.

Add the cooled milk mixture to the butter mixture. If the milk mixture is not cool, it will melt the butter and mess up the consistency of your frosting. Continue beating until the frosting is light and fluffy. Be sure to scrape down the bowl at least once while mixing to ensure all of your frosting is well combined. It will look like whipped cream when it is done.

On a plate (or whatever you want to serve the cake on), place one of the cake layers. I prefer to put the bottom cake layer top down so that I have a smooth surface to work with for the next layer. This usually saves me the step of trimming the top of the cake to make it level.

Spread a thin layer of frosting over the cake layer. This is to keep the next layer in place.

Unwrap the cookie dough layer and place it on top of the frosted cake layer.

If needed, trim the cookie dough layer so that it is the same size as the cake layer underneath. Once trimmed, spread a thin layer of frosting over the cookie dough layer.

Alternatively you can frost the cookie dough layer first and trim the cookie dough layer after applying the second cake layer. This may be easier since you will have a top and bottom layer to use as a guide instead of only the bottom layer as a guide.

Place the second cake layer on top of the frosted cookie dough layer. I usually place this cake layer top side up so that my flattest side of the cake is facing the previous layer. This minimizes any gaps that may have to be filled with frosting.

If you didn't trim the cookie dough layer in the previous step, trim it now if it needs to be trimmed so that the cake is even before you begin to add frosting.

Starting with sides of the cake, apply frosting to the cake. Once the sides of the cake are frosted, spread frosting over the top of the cake. The thickness of the frosting is entirely up to you. I usually have a little frosting left over after frosting this cake.

Allow the cake to sit for at least an hour so the frosting can set before cutting it.