Easy Chocolate Sheet Cake with Fudgy Chocolate Frosting
Easy Chocolate Sheet Cake with Fudgy Chocolate Frosting

This easy chocolate sheet cake recipe is the ultimate solution for anyone craving a delicious, crowd-pleasing dessert that’s simple to make and perfect for sharing. Whether you’re hosting a party, heading to a potluck, or just want a family-friendly weeknight treat, this moist one-pan chocolate cake with rich cocoa frosting will become your new go-to recipe!
Ingredients

For the Cake:
- 2 cups all-purpose flour
- 2 cups granulated sugar
- 1 cup unsalted butter
- 1 cup water
- 4 tablespoons cocoa powder
- 1 teaspoon baking soda
- 1/2 cup buttermilk
- 2 large eggs
- 1 teaspoon vanilla extract
For the Fudgy Frosting:
- 1/2 cup unsalted butter
- 4 tablespoons cocoa powder
- 6 tablespoons milk
- 1 teaspoon vanilla extract
- 3 1/2 cups powdered sugar
- 1 cup chopped walnuts or pecans (optional)
Step-by-Step Instructions
Step 1: Prepare the Cake Batter
Preheat oven to 350°F (175°C). Grease a 9×13 inch baking pan. In a large mixing bowl, combine flour and sugar.
Step 2: Make the Chocolate Mixture
In a saucepan, melt butter with water and cocoa powder over medium heat, stirring constantly until smooth. Bring to a boil, then remove from heat.
Step 3: Combine Ingredients
Pour the hot chocolate mixture over the flour and sugar. Mix well until combined. Add baking soda, buttermilk, eggs, and vanilla extract. Stir until smooth.
Step 4: Bake the Cake
Pour batter into prepared pan and bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean.
Step 5: Prepare the Frosting
While the cake is baking, make the frosting. Melt butter with cocoa powder and milk in a saucepan. Bring to a boil, then remove from heat. Stir in vanilla extract and gradually add powdered sugar until smooth. Stir in nuts if using.
Step 6: Frost the Cake
Pour the warm frosting over the hot cake as soon as it comes out of the oven. Spread evenly and let cool completely before serving.
Expert Tips
- For extra moist cake, don’t overmix the batter after adding the wet ingredients
- Make sure the frosting is poured over the hot cake so it soaks in slightly
- For a richer flavor, use high-quality cocoa powder
- The cake freezes well – perfect for make-ahead parties
- Add a pinch of cinnamon to the frosting for a Mexican chocolate twist
Frequently Asked Questions
Can I make this cake gluten-free?
Yes! Simply substitute the all-purpose flour with your favorite gluten-free flour blend.
How long does this cake stay fresh?
Properly stored in an airtight container, this cake stays moist and delicious for up to 3-4 days.
Can I make this cake ahead of time?
Absolutely! Bake the cake a day ahead, then frost it just before serving for best results.
What makes this a “sheet cake”?
Sheet cakes are baked in shallow rectangular pans, making them perfect for feeding crowds and easy slicing.

Easy Chocolate Sheet Cake with Fudgy Chocolate Frosting
Ingredients
Method
- Preheat oven to 350°F (175°C). Grease a 9×13 inch baking pan. In a large mixing bowl, combine flour and sugar.
- In a saucepan, melt butter with water and cocoa powder over medium heat, stirring constantly until smooth. Bring to a boil, then remove from heat.
- Pour the hot chocolate mixture over the flour and sugar. Mix well until combined. Add baking soda, buttermilk, eggs, and vanilla extract. Stir until smooth.
- Pour batter into prepared pan and bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean.
- While the cake is baking, make the frosting. Melt butter with cocoa powder and milk in a saucepan. Bring to a boil, then remove from heat. Stir in vanilla extract and gradually add powdered sugar until smooth. Stir in nuts if using.
- Pour the warm frosting over the hot cake as soon as it comes out of the oven. Spread evenly and let cool completely before serving.
