Are you loving this series as much as I am? I cannot wait to continue to share with you these fun sheet cakes for the next couple of weeks. I have some fun cakes in store, so surely you’ll find one you’re inspired to make for your next gathering! Next up – the best cookies and cream sheet cake!

Cookies and cream is such a classic flavor. I included it in my Cake Confidence cookbook, but felt like it needed a spot on Baking with Blondie. And no better way than to share it as a tasty sheet cake! Let’s dive right in, because with these mouthwatering photos, I can’t help but think of anything else other than eating a huge slice of this cake!

Do I have to make it into a sheet cake?

Nope! You can make it into three 6″ cakes, two 8″ cakes, a bundt cake, cupcakes, or even a rolled cake if you prefer! Just change the baking time and you’re all set. This sheet cake is easy to make, so I suggest trying it this way first, then branching out onto the other methods if you feel ready to stack a cake, etc.

What 9×13 pan do I need?

I personally used this one, but you can certainly use a glass one, etc. If you’d like to serve it outside of the pan, just flip it out onto the serving platter before you frost it. The crust will be on top, heads up, for this one, though, so you may have to get creative.

Ingredients for the cookies & cream cake:

Here’s what you’ll need:

  • Buttermilk
  • Sour cream
  • egg whites + egg
  • vegetable oil
  • vanilla
  • mini chocolate chips
  • cookies – pulsed into a powder
  • butter – for the crust
  • White Cake Mix box (I used Duncan Hines)

The directions are below for how to make the crust and the cake batter. You don’t need to pre-bake the crust. Just spread the batter out onto the crust and you’re all set.

How to make buttercream stripes

First of all, you’ll need this scraper – it’s a striped cake scraper and makes these clean indents (see video below for the process).

  • Spread out the buttercream.
  • Use the striped cake scraper to make clean stripe indents on the surface.
  • Freeze for 20 minutes to set the buttercream.
  • Pipe in the white buttercream.
  • Use a cake scraper to smear the white into the indents, then keep scraping to show the stripes through. Keep scraping and they’ll show, I promise!

Do i have to do buttercream stripes?

Nope! Just spread on the buttercream, add on a few crumbles and swirls, and top it off with some whole Oreos and you’ll be all set. It will still be just as tasty!

What if I don’t have a food processor?

That’s okay, but you’ll need to make sure to really crush those oreos into a fine powder to make a better crust that holds it’s shape when pressed flat.

How do I slice this cake?

I know that first slice can be a bit of a doozy, but if you freeze the cake for about 10 minutes to set everything, the slices are going to come out more clean. Use a sharp hot knife to cut through that thick delicious oreo crust, then use a spatula to life it out.

How many slices can I get out of this cake?

As many as you’d like! We got quite a few, but it also depends on how big the servings are you’re looking for. Smaller slices, more slices. Bigger slices, less slices. People can fight for that corner piece with the extra oreos, too. 🙂

Here’s a video of the process:

As always, if you make one of my cakes or bakes, I’d love to see it! Make sure to tag me @bakingwithblondie #bakingwithblondie so I can join in on all the fun!

Happy baking!

xx, Mandy

Get the Recipe: The Best Cookies & Cream Sheet Cake

5 from 1 vote
Delicious cookies and cream sheet cake with an Oreo cookie crust, white cake with bits of mini chocolate chips (or oreo crumbles), two-toned cookies & cream buttercream
Servings: 20 square slices
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Ingredients
 

Cookies & Cream Cake with Oreo Crust

  • 3 cups Oreo crumbles (about 24 -26 cookies with the filling), (3 cups measured after pulsing into a powder)
  • 5 Tablespoons unsalted butter, melted
  • 3/4 cup buttermilk , room temperature
  • 2/3 cup sour cream, room temperature
  • 3 egg whites, room temperature
  • 1 whole egg, room temperature
  • 1 Tablespoon vanilla
  • 1/3 cup vegetable oil
  • 1/4 cup mini chocolate chips OR crushed oreos
  • 1 15.25oz White Boxed Cake Mix (I used Duncan Hines)

Cookies & Cream Buttercream

  • 8oz cream cheese brick
  • 1 cup (or 2 sticks) unsalted butter
  • pinch of salt
  • 1 Tablespoon vanilla
  • 1/4 cup heavy cream
  • 7-8 cups powdered sugar
  • 1/2 cup oreo cookies powder (about 10-15 cookies), Only add the cookie powder AFTER you've reserved a little bit of buttercream for the white stripes. Skip this step if you're not using the stripes.

Extras

  • 1/2 cup oreo cookie powder
  • 1/2 cup mini chocolate chips
  • whole oreos

Equipment

  • 9×13 sheet pan
  • stripe cake scraper
  • 1M Piping Tip
  • food processor
  • Offset Icing Spatula or flat cake scraper

Instructions
 

Cookies & Cream Cake with Oreo Crust

  • Preheat the oven to 325 degrees, prep a 9×13 cake dish with a swipe of shortening and dust of flour. Set aside.
  • Pulse the cookies in a food processor into a fine powder, then pour in the melted butter. Pulse again to combine, or stir together in a separate bowl. Press the crust into the prepared dish and flatten evenly with the bottom of a glass or flat measuring cup. No pre-bake required.
  • Make the batter by stirring together all the ingredients except for the cake mix. Sift in the cake mix and gently stir to combine completely. Pour directly onto the crust and spread flat. Bake for 27-30 minutes until the center is finished baking – cool the cake in the pan completely before frosting the cake.

Cookies & Cream Buttercream

  • In the bowl of a stand mixer fitted with a paddle attachment, whip up the cream cheese and butter until they're thoroughly combined and light and fluffy.
  • Add in the salt, vanilla, and heavy cream and mix to combine. Add in the powdered sugar with the mixer speed on low and a little at a time. Flip the mixer on the highest speed for about 2 minutes to add texture and lightness to the buttercream. Reserve 1 cup of buttercream in a piping bag with no piping tip. Set aside.
  • To the rest of the buttercream, add in the Oreo cookie powder to make the cookies & cream buttercream. Using a wooden spoon, beat out the air bubbles to make the buttercream more smooth and silky.

Assembly

  • Reserve a couple cups of buttercream and add it to a piping bag with a 1M piping tip. Set aside for the swirls.
    Spread the rest of the Cookies & Cream buttercream onto the sheet cake, then use a cake scraper to make it smooth. Use a stripe cake comb to make the stripe indents. The neater the indents, the neater the stripes. Freeze the cake for 20 minutes.
  • Pipe in the reserved white buttercream stripes, then use a flat cake scraper over top the lines to make the stripes show through. Keep scraping and have patience, the stripes will slowly come.
  • Add on the Oreo crumbles around the outside border, then pipe on the cookies & cream swirls around the outside of the cake. Place on the oreo cookies between each swirl, then sprinkle on the mini chocolate chips. Enjoy!