We’re back in this fun sheet cake series with something that I know you’re going to love! How do I know? Well, I’ve already shared this recipe before :). However, with my sheet cake series, I wanted to create a fun way for cakes to be accessible for ALL – whether you’re stacking your cake or need to serve it in a sheet cake style for your gatherings. I have the best chocolate mint sheet cake for you today, and I’ve added a fun way you can decorate it so it can still be fun to make, fun to look at, and especially fun to eat!

Sheet cake love

I LOVE that you guys have been loving my sheet cake series so far – there’s still lots more to come! Hopefully you’ll find an idea to inspire you to apply to your upcoming sheet cakes. I know I’ve had a lot of fun making them so far.

How to make a chocolate mint cake

The mint cake is SUPER EASY. Like, stupid easy.

Just grab a large bowl and a whisk and you’re ready to go!

Here’s the ingredients you’ll mix together for the best chocolate mint sheet cake:

  • Buttermilk – room temperature. You can also make your own with vinegar/lemon juice and whole milk.
  • Sour Cream – room temperature.
  • Eggs + Egg White – room temperature, and I always use large sized eggs.
  • Vegetable Oil – You may use melted butter, too.
  • Vanilla – just a tablespoon will do.
  • Mint – I used mint extract. It can go from mint to toothpaste in ten seconds, so start with a little bit and taste to see if it’s too much or too little.
  • Flour – just 1/4 cup.
  • Cocoa – I used my typical brute cocoa that I love. You can find it here.
  • Mini Chocolate Chips – these are kind of optional, but add a little pocket of melty chocolate all around the cake layers, and it’s super tasty!
  • Duncan Hines Dark Chocolate Cake Mix – This is the one I used.

The directions are below with the recipe! Just make sure to not overmix, and the batter will be SUPER thick.

How to make mint cream cheese buttercream

Using your stand mixer, whip up everything together with a paddle attachment. Remember to let the butter and cream cheese combine fully before adding in anything else. For a creamy buttercream, this step is essential.

Ingredients you’ll need:

  • Butter – unsalted and left out at room temperature for 10 minutes so it can easily blend with the cream cheese.
  • Cream Cheese – I used the whole brick. Don’t let it soften before using it. It needs to be cold so it can avoid getting goopy.
  • Salt – just a little to cut through the sweets.
  • Vanilla – Use your good quality vanilla for your buttercream.
  • Mint – I used this kind and have loved the flavor.
  • Heavy Cream – I love the 40% Darigold brand. Don’t add too much or your buttercream will be too goopy.
  • Powdered Sugar – no need to sift, but you will need to turn the speed down on the mixer and add in a little bit at a time so you don’t have it flying everywhere in the kitchen!
  • Green Gel – to get that soft mint hue, just add in 1 drop, maybe two.

The directions are below with the recipe as to how it all comes together.

Striped ganache

I’ve never seen this technique before on a sheet cake, so I knew I wanted to give it a try! Here’s what you’ll need and how to pull it off:

  1. Smooth the buttercream flat with a cake scraper.
  2. Pull the stripe cake scraper (I used this one) and then make clean indents in the smooth buttercream. The neater the indents, the neater the stripes. Don’t be afraid to smooth it out and try again.
  3. Freeze the cake for 15 minutes to set the buttercream.
  4. Pipe or squeeze in the ganache into the stripe indents, then Tap the cake pan to let the stripes spread into their indents neatly. Repeat with the remaining stripes.
  5. Pipe on the details and sprinkle on the chocolate shavings.

Here’s a video of the process:

I can’t wait to see all your frosted sheet cakes! Make sure to tag me @bakingwithblondie #bakingwithblondie on social media so I can join in on all the fun!

Happy Baking,

xx, Mandy

Get the Recipe: The Best Chocolate Mint Sheet Cake

Decadent chocolate cake with cream cheese mint buttercream, ganache stripes, and chocolate shavings!
Servings: 20 servings, depending on slice size
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Ingredients
 

  • 3/4 cup buttermilk, room temperature
  • 2/3 cup sour cream , room temperature
  • 3 whole eggs, room temperature
  • 1 egg white
  • 1/3 cup vegetable oil
  • 1 Tablespoon vanilla
  • 1 teaspoon mint extract
  • 1/4 cup flour
  • 1/4 cup cocoa powder
  • 1/2 cup mini chocolate chips
  • 1 15.25oz Duncan Hines Box Cake Mix, I used "Dark Chocolate Fudge", but anything similar from other brands is fine.

Cream Cheese Mint Buttercream

  • 2 sticks (or 1 cup) unsalted butter, left out at room temperature for 10 minutes
  • 8oz brick cream cheese
  • pinch of salt
  • 1 Tablespoon vanilla
  • 1/2-1 teaspoon mint extract (1/2 if you want it less minty. 1 teaspoon if you want it to be full minty).
  • 1/4 cup heavy cream
  • 7-8 cups powdered sugar
  • 1-2 drops light green food gel coloring

Ganache

  • 1-2 cups Ghirardelli melting chocolate wafers
  • 1/4 cup heavy cream

Extra

  • 1 cup chocolate shavings

Equipment

  • stripe cake scraper
  • 869 Ateco piping tip
  • 9×13 sheet pan

Instructions
 

For the Chocolate Cake

  • Preheat the oven to 325 and prep a sheet cake pan (9×13) with nonstick spray or shortening + flour. Set aside.
  • In a large bowl, whisk together all the cake ingredients except for the cake mix. Sift in the cake mix (batter will be super thick), and stir until it's all combined (don't overmix!). Spread the batter out onto the prepared sheet cake pan.
  • Bake the cake for 25-27 minutes, then let cool completely in the pan before adding on the frosting.

For the Buttercream

  • In the bowl of a large stand mixer, whip up the butter an cream cheese until they're both light and fluffy (no little white bits!), about 1 minutes on medium speed.
  • Add in the salt, vanilla, mint extract, and heavy cream and mix to combine. With the mixer on low speed, add in the powdered sugar about 1/2 cup at a time, then turn on the mixer to the highest speed for 2 minutes to help make the buttercream light and fluffy again. Add in the food coloring, and mix again. If it's too soupy, you need more powdered sugar OR you can place it in the fridge for 20 minutes to bring the butter and cream cheese back to a more cooled temperature.
    Use a wooden spoon to beat out any air bubbles to create a smooth texture.

Ganache

  • Heat the chocolate and heavy cream in the microwave for 30 seconds, stir. Add another 30 seconds and stir again until it's smooth. Add to a squeeze bottle and set aside.

Assembly

  • Fill a piping bag fitted with a large french star piping tip with buttercream, then set aside.
  • With the remaining buttercream, gently spread on a flat layer with an offset icing spatula and smooth it flat with a flat cake scraper.
  • Using a stripe cake scraper with indents, create clean indents in the buttercream. If it doesn't look clean (meaning, clear lines), add on some buttercream in those flawed areas, and scrape again. Clean lines will equal clean stripes, so this step is essential to get right. Be patient, and those lines will appear!
  • Freeze the cake for 15 minutes, until the buttercream is firm. Make the ganache.
  • Pipe in the ganache into the clean indents, and tap the cake flat after each one to spread the ganache into the indent to create a stripe. Repeat with the remaining stripe indents.
  • Pipe line of shells on the two short ends of the cake, then in the center, then between each one so you end up with 5 lines of shell borders.
  • Sprinkle on the chocolate shavings, and enjoy!