Chocolate Sheet Cake with Mint Buttercream


The mask mandate has been lifted here in Luxembourg, and today was the first time in two years that I’ve taken my kids to school and went to the grocery store without a mask on. I admit it feels strange. Like I’m doing something naughty. 😂 I don’t feel naughty at all eating this Chocolate Sheet Cake with Mint Buttercream. The cake is super moist with plenty of chocolate flavor. The buttercream is a Swiss meringue buttercream with mint extract and it tastes so good with the chocolate.

chocolate sheet cake with mint buttercream

This recipe starts with our decadent chocolate cake that bakes up beautifully in a 9×13 aluminum sheet pan. My favorite is this pan by USA Bakeware because it has perfectly straight edges. Then we make a beautiful Swiss meringue buttercream flavored with mint extract. I add a drop of green food coloring for pizazz. 😉

Happy Baking!


Chocolate Sheet Cake with Mint Buttercream

Recipe by Amanda Innes-ShareefCourse: DessertDifficulty: Easy


Cooking time






  • All Purpose Flour 240g
    (1 1/2 cups)

  • Sugar 300g
    (1 1/2 cups)

  • Dark cocoa 85g
    (3/4 cup)

  • Espresso Powder 1 tsp

  • Baking Soda 1 1/2 tsp

  • Baking Powder 1 tsp

  • Salt 1 tsp

  • Buttermilk 200g
    (3/4 cup)

  • Vegetable Oil 95g
    (1/2 cup)

  • 2 Eggs

  • Hot Coffee 170g
    (3/4 cup)

  • 1 Recipe Mint Swiss Meringue Buttercream (recipe below)


  • Preheat oven to 325°. Spray a 9×13 pan. OR spray and parchment three 6″ round cake pans. OR spray and parchment two 8″ round cake pans.
  • Add dry ingredients to medium sized mixing bowl and whisk to ensure all ingredients are combined.
  • In a separate bowl, whisk together vegetable oil, buttermilk and eggs.
  • Add wet ingredients to dry ingredients and beat just until combined.
  • Add HOT coffee and mix again just until combined. Use a spatula to scrape down the sides of the bowl.
  • Bake for 22-24 minutes, or until a toothpick inserted comes out clean.
  • Cool completely. Spread mint buttercream on top (recipe below).


  • Make sure all of your wet ingredients are room temperature. I like to leave my eggs out overnight and I microwave my buttermilk for about 30-45 seconds before using.
  • You can also make 18 cupcakes with this recipe but reduce the baking time to 18-20 minutes.

mint swiss meringue buttercream Directions

  • Pour 2 inches of water into a small saucepan or bain marie and bring to a boil.
  • In the bowl of a stand mixer, add 180g egg whites (about 6 egg whites), 400g sugar (2 cups), and a pinch of salt.
  • Place the bowl over the saucepan so that no steam escapes. Whisk vigorously until a white foam appears on the surface. Test the mixture with your fingers. If you rub your fingers together and you can’t feel any sugar granules, it’s ready.
  • Remove from the heat and place the bowl on the stand mixer. Whisk on high speed for at least 10 minutes.
  • When the bowl is cool to the touch, switch to the paddle attachment and beat in 339g butter (1 1/2 cups) in chunks. Beat on high until the buttercream comes together.
  • Add 1/2 tsp mint extract and beat until combined. Add a drop of green food coloring and beat until you achieve the color you want. You can add more food coloring to make it darker.