Chocolate Sheet Cake With Cocoa

Name: Chocolate Sheet Cake With Cocoa
Prep time: 15 min
Cook time: 30 min
Total time: 45 min
Yield: 12 servings
Ingredients: 2 cups all-purpose flour; 2 cups granulated sugar; 3/4 cup unsweetened cocoa powder; 1 1/2 teaspoons baking soda; 1 1/2 teaspoons baking powder; 1 teaspoon salt; 2 large eggs; 1 cup buttermilk; 1 cup vegetable oil; 2 teaspoons vanilla extract; 1 cup boiling water; 1/2 cup unsalted butter; 2/3 cup unsweetened cocoa powder; 3 cups powdered sugar; 1/3 cup milk; 1 teaspoon vanilla extract

Highlighted under: Cakes & Sweet Treats

I absolutely love making this Chocolate Sheet Cake with Cocoa whenever I have a celebration or just want to bake something delightful. The rich chocolate flavor combines beautifully with the light, moist texture that everyone adores. It’s an easy recipe that doesn’t require any fancy equipment or techniques, making it perfect for bakers of all skill levels. With just a few ingredients, I can whip up this delicious dessert that never fails to impress family and friends. Plus, it’s an ideal treat for potlucks and parties!

Created by

Noelle Chambers

Last updated on 2026-02-01T19:03:36.752Z

Baking this Chocolate Sheet Cake with Cocoa has become a cherished tradition in my kitchen. Every time I take it out of the oven, the aroma of chocolate wafts through my home, inviting everyone to gather around. I remember the first time I made it—I was worried about the texture, but it turned out perfectly moist and fluffy. The key was using quality cocoa powder and ensuring I didn’t overmix the batter.

Every bite of this cake is pure joy, and I’m always surprised by how quickly it disappears! I like to add a simple chocolate glaze on top, which elevates the cake without complicating the process. It’s a no-fail recipe that brings happiness to every occasion!

Why You'll Love This Recipe
Rich chocolate flavor paired with fresh orange zest
Creamy texture that melts in your mouth
Perfect for celebrations or as a sweet indulgence

The Importance of Each Ingredient

Each ingredient in this Chocolate Sheet Cake plays a crucial role in achieving its signature flavor and texture. For instance, using unsweetened cocoa powder, rather than sweetened, ensures that the cake maintains the rich chocolate flavor without becoming overly sweet. The buttermilk not only moistens the batter but also reacts with the baking soda to create a light, airy texture, providing a lovely crumb structure that’s both soft and substantial.

It's essential to use fresh baking powder and baking soda, as these leavening agents are key to achieving that perfectly risen cake. If you’re out of buttermilk, a quick substitute can be made by mixing one cup of milk with a tablespoon of vinegar and letting it sit for about 10 minutes. This mimicry of buttermilk’s acidity helps ensure that your cake rises beautifully.

Expert Baking Techniques

When preparing the batter, don't overmix after adding the wet ingredients. Just mix until everything is combined; overmixing can lead to a dense cake, which would detract from the light, moist texture we’re aiming for. After you pour in the boiling water, which may seem unusual, understand that it intensifies the chocolate flavor and helps create a thinner batter that ultimately yields a wonderfully moist cake.

For baking, I recommend checking the cake at the 30-minute mark. Every oven heats differently, and a toothpick inserted into the center should come out clean or with a few moist crumbs, not wet batter. If it's underbaked, return it to the oven for another couple of minutes, checking frequently to prevent overbaking, which can dry out the cake.

Ingredients

For the Cake

2 cups all-purpose flour
2 cups granulated sugar
3/4 cup unsweetened cocoa powder
1 1/2 teaspoons baking soda
1 1/2 teaspoons baking powder
1 teaspoon salt
2 large eggs
1 cup buttermilk
1 cup vegetable oil
2 teaspoons vanilla extract
1 cup boiling water

For the Glaze

1/2 cup unsalted butter
2/3 cup unsweetened cocoa powder
3 cups powdered sugar
1/3 cup milk
1 teaspoon vanilla extract

Instructions

Preheat the Oven

Preheat your oven to 350°F (175°C). Grease and flour a 12x17-inch baking sheet.

Mix Dry Ingredients

In a large bowl, whisk together the flour, granulated sugar, cocoa powder, baking soda, baking powder, and salt until well combined.

Add Wet Ingredients

Add eggs, buttermilk, vegetable oil, and vanilla extract to the dry ingredients. Mix until just combined.

Add Boiling Water

Stir in the boiling water carefully; the batter will be thin.

Bake the Cake

Pour the batter into the prepared baking sheet and bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean.

Prepare the Glaze

While the cake is baking, melt the butter in a saucepan over medium heat. Stir in cocoa powder, then add powdered sugar and milk gradually. Mix until smooth.

Glaze the Cake

Once the cake is done, remove it from the oven and let it cool for 10 minutes. Pour the glaze over the warm cake and spread it evenly.

Serve

Allow the cake to cool completely before slicing and serving.

Pro Tips

For an even richer flavor, consider adding a teaspoon of espresso powder to your batter. Chocolate sheet cake also pairs beautifully with fresh berries for a decorative touch.

Storing and Freezing

This Chocolate Sheet Cake is great for keeping as leftovers! Once it's completely cooled, you can cover it with plastic wrap or transfer it to an airtight container. Stored properly at room temperature, it can last for 3 to 4 days. If your cake is glazed, keep it in the fridge to maintain its freshness, ensuring the glaze stays smooth and doesn’t harden up too much.

If you want to prepare it ahead of time, this cake freezes exceptionally well. Slice it into individual portions and wrap each slice tightly in plastic wrap, then place them in a freezer-safe bag. It can be frozen for up to 3 months. When you're ready to enjoy it, simply thaw it in the refrigerator overnight or at room temperature for a few hours.

Serving Suggestions

This cake can be served plain, but for an extra indulgence, consider adding a scoop of vanilla ice cream or a dollop of whipped cream. A sprinkle of orange zest over the top before serving enhances the flavor and adds a touch of elegance that complements the chocolate beautifully. You can also serve it alongside fresh berries for a nice contrast and a pop of color on the plate.

For more variation, consider turning it into a layered dessert. Cut the sheet cake into squares and layer it with chocolate mousse or custard in parfait glasses, topping it with whipped cream and chocolate shavings for an impressive presentation. This is not only visually appealing but also gives a delightful twist on the traditional sheet cake experience.

Questions About Recipes

→ Can I use whole wheat flour instead of all-purpose?

Yes, you can use whole wheat flour, but it may change the texture slightly. Expect a denser cake.

→ How do I store leftover cake?

Store the cake in an airtight container at room temperature for up to 3 days, or refrigerate for up to a week.

→ Can I freeze this cake?

Absolutely! Wrap individual slices in plastic wrap and place them in a freezer-safe bag. Thaw in the fridge when ready to eat.

→ What can I use instead of buttermilk?

You can make a homemade substitute by adding 1 tablespoon of lemon juice or vinegar to 1 cup of milk. Let it sit for 5 minutes to thicken.