Prep Time:
30 mins
Cook Time:
25 mins
Additional Time:
1 hr
Total Time:
1 hr 55 mins
Servings:
24
Yield:
1 sheet cake
Ingredients
1/2x
1x
2x
Original recipe (1X) yields 24 servings
Cake:
1 ¾ cups all-purpose flour
1 cup dark cocoa powder (such as Hershey’s® Special Dark)
2 teaspoons baking soda
½ teaspoon salt
1 cup firmly packed dark brown sugar
½ cup white sugar
½ cup unsalted butter, softened
2 large eggs, at room temperature
2 teaspoons vanilla extract
1 cup strong brewed coffee, at room temperature
1 cup buttermilk, at room temperature
Frosting:
1 cup unsalted butter, softened
¾ cup dark cocoa powder (such as Hershey’s® Special Dark), sifted
1 teaspoon instant espresso powder
⅛ teaspoon salt
2 teaspoons vanilla extract
3 cups powdered sugar, or to taste
7 tablespoons heavy whipping cream, or as needed
Directions
Gather all ingredients.
all ingredients gathered to make dark chocolate sheet cake with dark chocolate frosting.
Dotdash Meredith Food Studios
Preheat the oven to 350 degrees F (175 degrees C). Grease a 10×15-inch rimmed baking sheet and line the bottom of the pan with parchment paper.
Whisk flour, cocoa powder, baking soda, and salt together in a bowl until thoroughly combined. Set aside.
Flour, cocoa powder and baking soda whisked together.
Dotdash Meredith Food Studios
Beat brown sugar, white sugar, and butter together in a large bowl with an electric mixer until light and fluffy. Beat in eggs one at a time, mixing well after each addition.
brown and white sugar, and butter beaten together, with eggs added one at a time.
Dotdash Meredith Food Studios
Mix in vanilla extract.
ingredients mixed until well combined and vanilla added.
Dotdash Meredith Food Studios
Add in 1/3 of the flour mixture, and mix until just combined.
1/3 of the flour mixture added and whisked together until combined.
Dotdash Meredith Food Studios
Add in 1/2 of the coffee and buttermilk, and mix until just combined.
1/2 of buttermilk and coffee added, mixing until just combined.
Dotdash Meredith Food Studios
Continue alternating additions of the flour mixture with coffee and buttermilk, mixing just until combined.
additions of flour, buttermilk and coffee added, mixing until just combined.
Dotdash Meredith Food Studios
Pour batter into the prepared pan; smooth into an even layer. Tap pan firmly on the counter several times to remove air bubbles.
batter poured into prepared pan and spread evenly.
Dotdash Meredith Food Studios
Bake in the preheated oven until a toothpick inserted into the center of the cake comes out with a few moist crumbs, about 25 minutes. Do not overbake. Place cake on a wire rack and allow to cool completely.
bake until a toothpick comes out clean.
Dotdash Meredith Food Studios
Meanwhile, make the frosting. Beat butter in a large bowl until completely smooth.
butter beaten until completely smooth.
Dotdash Meredith Food Studios
Mix in cocoa powder, espresso powder, and salt until throughly combined. Mix in vanilla.
cocoa powder, espresso powder, salt and vanilla mixed until combined.
Dotdash Meredith Food Studios
Add in powdered sugar 1 cup at a time, mixing well after each addition.
powdered sugar added to mixture one cup at a time, mixing well.
Dotdash Meredith Food Studios
Pour in heavy cream and beat until frosting is light and fluffy, 2 to 3 minutes. If frosting is too thick, add more heavy cream.
heavy cream added until frosting is light and fluffy.
Dotdash Meredith Food Studios
Spread frosting over the cooled cake.