Oreo Brownies

Intensive Cake Unit
by Intensive Cake Unit
1 Sheet cake
50 min

Sometimes I need a dessert that’s simple and goes together quickly! A decorated 9x13 sheet pan of cake or brownies can easily be made from scratch OR doctored-up mixes, and they’re easy to decorate, festive, delicious, and can serve a large crowd - I hate boring sheet cakes, so I spiced this one up by piping on the frosting and adding some texture with Oreo halves! Recipe below!

Like any sheet cake, you have tons of options here! If you’d rather doctor up brownie mixes, use two mixes (I usually go with Ghiradelli), substitute butter for the oil, replace the water with milk, and add an extra egg!

If brownies *and* frosting isn't your thing, you can also use a regular chocolate sheet cake – my go-to layer cakes bakes pretty dense – this Chocolate Sheet Cake recipe by ThePioneerWoman is a recipe that bakes a great looking cake and features buttermilk, which I love in chocolate cake recipes!

Recipe details
  • 1  Sheet cake
  • Prep time: 10 Minutes Cook time: 40 Minutes Total time: 50 min
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  • 1 cup unsalted butter (or 2 sticks) melted
  • 1 cup granulated sugar
  • 1 cup brown sugar
  • 4 large eggs
  • 6 Tablespoons unsweetened cocoa powder
  • 3/4 teaspoon baking powder
  • 1 teaspoon salt
  • 1 1/2 cups all-purpose flour
  • 1 Tablespoon vanilla extract
  • 1 ½ cups semi-sweet chocolate chips
Cream Cheese Buttercream Frosting:
  • 8 oz (one package) cream cheese, softened
  • 16 Tablespoons (two sticks) butter, softened
  • 6-7 c powdered sugar 2-4 Tablespoons milk
  • 1 T clear vanilla extract
  • 1/4 t. salt (if using unsalted butter)
  • (Save and add later! 1-2 large drops Americolor Navy Blue and Americolor Super Red – I used these to make a deep purple color that I loved! You could also use Americolor Regal purple and add just a bit of Americolor Super Black.
Additional Supplies / Decorations:
  • - 6-12 Oreo cookies (I broke mine in half for ease of decorating, but you could absolutely use whole ones!
  • - Large piping bag & tip – I use this set of reusable large bags & tips more than almost any of my others!
  • Small piping bag & tip – this set has been one of my favorites, and contains the small star and teardrop-tips I used to pipe the brownies in the photos/video
  • Sprinkle mix of your choice! – I used ‘Pastel’ Sprinkle Mix by Sweet Tooth Fairy; I couldn’t find it online but their Unicorn Mix is similar and I love the colors!
Preheat oven to 350°F. Grease a 9x13 baking pan with non-stick or baker’s floured cooking spray.
Mix together melted butter and granulated and brown sugars. Whisk in eggs until well combined. Whisk in cocoa powder, baking powder, salt, and gradually stir in all-purpose flour until combined. Stir in vanilla and chocolate chips, and pour into prepared pan.
Bake for 35-37 minutes (or until a toothpick comes out clean). Cool completely before frosting. Set in the fridge or freezer to accelerate the cooling process if desired.
This is a great time to make your frosting!
Frosting / Decorating
Beat together softened cream cheese and butter; slowly add in powdered sugar alternating with milk until frosting reaches desired consistency. Add vanilla and salt if needed and beat until well combined.
Divide your frosting in half, and color one half purple – leave the other half white. I used the large open star from my large tip set and a smaller open star and oblong teardrop-shaped tip from my smaller set when I piped the frosting onto the brownies – and I usually find it easiest to start with the larger tips and fill in around them with smaller designs. Up to you!
Add sprinkles to your liking – I started with larger ones spaced where I thought they looked best and then added smaller ones in between them. You could also skip the ‘placement’ and just sprinkle them over the top – either works but sometimes the second one’s more fun!
Annnd you’re done! High-five yourself –and enjoy!
Make this recipe? Let me know how it went - or find me on Pinterest or on Instagram and tag @IntensiveCakeUnit in your photo!
  • Note - the frosting recipe makes a generous amount; feel free to halve the recipe if you're not a frosting fanatic like I am!
Intensive Cake Unit
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