Classic Yellow Sheet Cake with Chocolate Buttercream
Soft yellow cake baked into a sheet cake form, with the most decadent soft chocolate buttercream, topped with all the rainbow sprinkles… this cake is fit for any party!
This is such a classic flavor that should be in anyone’s baking repertoire. My husband requests it frequently for his birthday cake flavor pick, and I happily make it for him. Why? Because it’s SO tasty and super easy to make! And is it not just the happiest cake you’ve ever seen?
It also is my next cake in my fun sheet cake series! So far we’ve had 5 delicious sheet cakes, and we still have 5 more to share, including this one! Hopefully as I’ve shared these sheet cakes, you’ve been able to find new cake flavors you’d like to try, but also new ways to decorate a sheet cake that you’ve never seen before. It’s been fun to step outside the usual stacked cake box, and have just as much fun decorating a sheet cake.
Let’s dive right into my classic yellow sheet cake with chocolate buttercream! Here’s what you’ll need to know:
ingredients for a classic yellow cake
The ingredients are super simple! You’ll need 5 simple things to add to your yellow cake mix. Yep! This is a doctored cake mix recipe – don’t knock it until you’ve tried it! It’s a perfect way to get a gorgeous looking AND tasting cake without the margin for error you can get from scratch cakes. Bakeries from all around the world use this method for beautiful cakes, and you can to!
- Buttermilk – room temperature
- Sour Cream – room temperature
- Eggs – whole large eggs, room temperature (noticing a theme?) 🙂
- Vegetable oil
- Vanilla
- Yellow cake mix – I prefer the Duncan Hines brand.
The beauty of this cake batter is that you don’t need a stand mixer for this part. Just a whisk and a bowl! Mix it together and spread it into your 9×13 baking dish.
What 9×13 cake pan is that?
For this particular cake, I used this OXO 9×13 pan, but you can use a glass one or any others that are similar size!
Can I make it into something else?
If you’d like to make this into a three layer 6″ cake, do it!
Two 8″ layers? You’ve got it!
Bundt cake? Yes! Just add on a bit more baking time.
Cupcakes? Perfect! Split them into 24 cupcakes and bake for 12-15 minutes.
This recipe is so versatile and easy to change into different forms of cake. In my Cake Confidence cookbook and I’ll Bring the Cake cookbook, it’s in a 6″ cake form.
where can i find those sprinkles?
I usually buy them in bulk here, but you can always find them at your local grocery store in the baking section.
How to make chocolate buttercream
This buttercream uses BOTH cocoa and chocolate in it! Double the chocolate for extra chocolate flavor, right? Here’s what you’ll need to know for my Classic yellow sheet cake with chocolate buttercream:
Make the ganache by melting chocolate and heavy cream together in the microwave (only do 30 seconds and stir at a time!). Let it cool.
Whip up the butter in the stand mixer with a paddle attachment until it’s light and fluffy. It’s best to start with butter that isn’t rock solid cold. I leave mine out at room temperature for 10-15 minutes beforehand.
Add in the salt, vanilla, cocoa, and cooled ganache.
Whip everything together, then add in the powdered sugar on the lowest speed, a little at a time.
If the buttercream is looking too thick, add in a little more heavy cream (about a Tablespoon at a time).
Turn the mixer on the highest speed to whip up the buttercream into a softer, lighter texture.
Beat the buttercream with a wooden spoon to get out any air bubbles (I didn’t do this step as diligently as I should have, and you can see all the air bubbles below!).
What piping tips are needed for this design?
I used a Wilton 127D & Ateco 869. You’ll also need some piping bags!
Here’s a video of the buttercream decorating process:
As always, I love to see your Baking with Blondie cakes and bakes! Make sure to tag me @bakingwithblondie #bakingwithblondie so I can join in on all the fun!
Happy Baking!
xo, Mandy
Get the Recipe: Classic Yellow Sheet Cake with Chocolate Buttercream and Sprinkles
Ingredients
Classic Yellow Cake
- 3/4 cup buttermilk, room temperature
- 2/3 cup sour cream , room temperature
- 3 whole eggs , room temperature
- 1/3 cup vegetable oil
- 1 Tablespoon vanilla
- 1 15.25oz Yellow Cake Mix (I used Duncan Hines)
Chocolate Buttercream
- 1 cup Ghirardelli chocolate melts or chocolate chips
- 1/2 cup heavy cream
- 1 1/2 cup (or three sticks) unsalted butter, left out at room temperature for 10-15 minutes
- 1 pinch salt
- 1 Tablespoon vanilla
- 1/4 cup cocoa powder
- 7-8 cups powdered sugar
Extras
- 1 cup rainbow sprinkles
Equipment
- Wilton 127 D Piping Tip
- Large French Piping Tip
- 9×13 Baking Pan
Instructions
For the yellow cake:
- Preheat the oven to 325 degrees. Prep the 9×13 sheet pan with shortening and flour, or baking spray. Set aside
- In a large mixing bowl, whisk together all the ingredients except for the cake mix until they're all combined. Sift in the cake mix, then gently stir to fully combine (no pockets of powdered cake mix!). Pour into the prepared baking pan and spread evenly.
- Bake for 25-27 minutes, then let cool completely before adding on the frosting.
For the chocolate buttercream:
- Heat the chocolate and heavy cream in the microwave for 30 seconds, then stir. Repeat and stir until smooth. Let cool until the ganache is closer to room temperature.
- In the bowl of a stand mixer fitted with a paddle attachment, whip up the butter until it's light and fluffy, about 1 minute. Add in the salt, vanilla, and cocoa powder. Add in the cooled ganache and whip up again. Scrape down the sides of the bowl, then add in the powdered sugar slowly until combined. (You may need to add in a little more heavy cream – start with 1 Teaspoon, and go from there).
- Flip the stand mixer to the highest speed, and let whip up for 2 minutes until the buttercream has lightened in texture and color. Use a wooden spoon to hand-beat out the air bubbles, then add the buttercream to two piping bags with the piping tips indicated above if decorating like I did. If not, slather on the buttercream with an offset icing spatula and add on the sprinkles.
- If using the piping tips, with the 127 D piping tip (wide end on the cake) pipe straight lines that slightly overlap to cover the cake. Use the large french tip to pipe a shell border around the outside rim, then add on the sprinkles. Enjoy!