Ultimate Indulgent Chocolate Sheet Cake with Fudgy Frosting

When you need a dessert that feeds a crowd without compromising on flavor, this indulgent chocolate sheet cake is your perfect solution. With its moist, rich chocolate base and velvety fudgy icing, this easy baking recipe delivers bakery-quality results using simple ingredients and one bowl. Whether you’re prepping for a potluck, celebration, or just craving a decadent chocolate treat, this crowd-pleasing cake comes together quickly and serves beautifully.

Ingredients

For the Cake:

• 2 cups all-purpose flour
• 2 cups granulated sugar
• ¾ cup unsweetened cocoa powder
• 2 teaspoons baking soda
• 1 teaspoon baking powder
• 1 teaspoon salt
• 1 cup vegetable oil
• 1 cup buttermilk
• 2 large eggs
• 1 cup strong brewed coffee, cooled
• 1 tablespoon vanilla extract

For the Fudgy Icing:

• ½ cup butter
• ¼ cup cocoa powder
• 6 tablespoons milk
• 1 teaspoon vanilla extract
• 3½ cups powdered sugar

Step-by-Step Instructions

Step 1: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking sheet with butter or cooking spray.

Step 2: In a large mixing bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt until well combined.

Step 3: Add vegetable oil, buttermilk, eggs, cooled coffee, and vanilla extract to the dry ingredients. Mix until just combined – be careful not to overmix the batter.

Step 4: Pour the batter into the prepared baking sheet and spread evenly. Bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean.

Step 5: While the cake bakes, prepare the fudgy icing. In a medium saucepan, melt butter over medium heat. Whisk in cocoa powder until smooth.

Step 6: Remove from heat and stir in milk and vanilla extract. Gradually whisk in powdered sugar until the icing is smooth and glossy.

Step 7: Pour the warm icing over the hot cake as soon as it comes out of the oven. Use a spatula to spread it evenly across the surface.

Step 8: Allow the cake to cool completely before slicing and serving.

Expert Tips

• For an extra-moist cake, use full-fat buttermilk and don’t overbake – the cake should spring back lightly when touched.

• The coffee enhances the chocolate flavor without making the cake taste like coffee. If you prefer to omit it, substitute with hot water.

• Make this cake ahead of time – it actually tastes better the next day as the flavors meld together.

• For special occasions, top with chocolate shavings or sprinkles before the icing sets.

If you love impressive desserts that are surprisingly simple to make, you’ll also enjoy our Ultimate Strawberry Crunch Cake or our moist Lemon Blueberry Yogurt Loaf.

Frequently Asked Questions

Can I make this cake without buttermilk?
Yes! Mix 1 cup milk with 1 tablespoon lemon juice or vinegar, let it sit for 5 minutes until curdled, then use as buttermilk substitute.

How should I store leftover cake?
Store covered at room temperature for up to 3 days, or refrigerate for up to a week. The cake freezes beautifully for up to 3 months.

Can I bake this in a different pan?
Yes, you can use two 9-inch round pans but reduce baking time to 20-25 minutes. For more dessert inspiration, check out our Easy Chocolate Sheet Cake variations.

Is this cake suitable for large gatherings?
Absolutely! This recipe serves 15-20 people, making it perfect for potlucks, celebrations, and parties. For more crowd-pleasing recipes, explore our collection.

Ultimate Indulgent Chocolate Sheet Cake with Fudgy Frosting

This indulgent chocolate sheet cake is perfect for feeding a crowd with its moist, rich chocolate base and velvety fudgy icing. Using simple ingredients and one bowl, this easy recipe delivers bakery-quality results for potlucks, celebrations, or chocolate cravings.

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 30 minutes mins

Total Time 45 minutes mins

Servings: 15 servings

Calories: 420

Ingredients Method Notes

Ingredients

  

Ingredients

• 2 cups all-purpose flour
• 2 cups granulated sugar
• ¾ cup unsweetened cocoa powder
• 2 teaspoons baking soda
• 1 teaspoon baking powder
• 1 teaspoon salt
• 1 cup vegetable oil
• 1 cup buttermilk
• 2 large eggs
• 1 cup strong brewed coffee, cooled
• 1 tablespoon vanilla extract
• ½ cup butter
• ¼ cup cocoa powder
• 6 tablespoons milk
• 1 teaspoon vanilla extract
• 3½ cups powdered sugar

Method

 

Instructions

1. Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking sheet with butter or cooking spray.
2. In a large mixing bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt until well combined.
3. Add vegetable oil, buttermilk, eggs, cooled coffee, and vanilla extract to the dry ingredients. Mix until just combined – be careful not to overmix the batter.
4. Pour the batter into the prepared baking sheet and spread evenly. Bake for 25-30 minutes, or until a toothpick inserted in the center comes out clean.
5. While the cake bakes, prepare the fudgy icing. In a medium saucepan, melt butter over medium heat. Whisk in cocoa powder until smooth.
6. Remove from heat and stir in milk and vanilla extract. Gradually whisk in powdered sugar until the icing is smooth and glossy.
7. Pour the warm icing over the hot cake as soon as it comes out of the oven. Use a spatula to spread it evenly across the surface.
8. Allow the cake to cool completely before slicing and serving.

Notes

For an extra-moist cake, use full-fat buttermilk and don’t overbake. The coffee enhances chocolate flavor without making it taste like coffee (can substitute with hot water). Cake tastes better the next day as flavors meld together. Top with chocolate shavings or sprinkles before icing sets for special occasions.