Indulge in the rich, velvety decadence of this Dark Chocolate Sheet Cake—a timeless treat for chocolate lovers. This moist and tender cake pairs the deep, bold flavor of unsweetened cocoa with a touch of buttermilk for a perfectly balanced sweetness. Topped with a luscious homemade chocolate frosting made from melted butter and cocoa powder, every bite is pure dessert bliss. Easy to make in just under an hour, this one-pan marvel is ideal for celebrations, potlucks, or simply satisfying your sweet tooth. Serve it sliced into generous squares and watch it disappear in no time! Perfect for lovers of chocolate cakes, simple baking, and crowd-pleasing desserts, this recipe is guaranteed to impress.
Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking pan and set it aside.
In a large bowl, whisk together the flour, granulated sugar, cocoa powder, baking powder, baking soda, and salt.
Add the buttermilk, vegetable oil, eggs, and vanilla extract to the bowl. Mix until the batter is smooth and well combined.
Carefully stir in the boiling water. The batter will be thin; this is normal.
Pour the batter evenly into the prepared baking pan.
Bake in the preheated oven for 30-35 minutes, or until a toothpick inserted into the center of the cake comes out clean.
While the cake cools, prepare the frosting. Melt the unsalted butter in a medium saucepan over low heat.
Stir in the cocoa powder until smooth and combined.
Remove the saucepan from the heat and alternately add the powdered sugar and milk, beating until the frosting reaches a spreadable consistency.
Stir in the vanilla extract.
Once the cake is completely cooled, spread the frosting evenly over the top of the cake.
Slice the cake into squares and serve. Enjoy!
Calories |
7644 | ||
|---|---|---|---|
% Daily Value* |
|||
| Total Fat | 365.5 g | 469% | |
| Saturated Fat | 172.6 g | 863% | |
| Polyunsaturated Fat | 67.7 g | ||
| Cholesterol | 922 mg | 307% | |
| Sodium | 5619 mg | 244% | |
| Total Carbohydrate | 1187.1 g | 432% | |
| Dietary Fiber | 134.6 g | 481% | |
| Total Sugars | 797.0 g | ||
| Protein | 117.5 g | 235% | |
| Vitamin D | 9.2 mcg | 46% | |
| Calcium | 931 mg | 72% | |
| Iron | 58.0 mg | 322% | |
| Potassium | 6066 mg | 129% | |
*The % Daily Value tells you how much a nutrient in a serving of food contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.