Chocolate Sheet Cake With Cocoa

Name: Chocolate Sheet Cake With Cocoa
Prep time: 15 min
Cook time: 20 min
Total time: 35 min
Yield: 12 servings
Ingredients: 2 cups all-purpose flour; 2 cups granulated sugar; 3/4 cup cocoa powder; 1 1/2 teaspoons baking soda; 1 1/2 teaspoons baking powder; 1 teaspoon salt; 2 large eggs; 1 cup whole milk; 1/2 cup vegetable oil; 2 teaspoons vanilla extract; 1 cup boiling water; 1/2 cup unsalted butter, softened; 2/3 cup cocoa powder; 3 cups powdered sugar; 1/3 cup milk; 1 teaspoon vanilla extract

Highlighted under: Home-Baked Happiness

When I think about baking, chocolate sheet cake is always at the top of my list! I love how simple it is to prepare, and yet it delivers an incredible flavor that can satisfy any chocolate lover's cravings. The rich cocoa combined with a luscious frosting creates an indulgent treat that is perfect for any occasion. Whether it’s a birthday celebration or just a Tuesday afternoon, this cake is my go-to for a quick and delicious dessert that everyone will appreciate.

Created by

Erin Wallace

Last updated on 2026-02-10T22:33:36.780Z

One of my favorite memories is making this chocolate sheet cake for our family gatherings. The combination of rich cocoa and fluffy frosting never fails to steal the show. I find that using hot water in the batter helps to bloom the cocoa, intensifying the chocolate flavor and ensuring a moist cake. The ease of preparation means I can whip it up quickly while enjoying the company of my loved ones.

After testing various frostings, I settled on a simple buttercream that perfectly complements the chocolatey base. The secret here is to cream the butter well before adding the powdered sugar, which results in a silky consistency that spreads wonderfully. Trust me, this cake will have everyone coming back for seconds!

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

Understanding Chocolate's Role

The cocoa powder in this chocolate sheet cake is essential, as it imparts that deep, rich chocolate flavor that everyone loves. I recommend using high-quality unsweetened cocoa powder for the best results. The cocoa powder not only fuels the chocolatey taste but also affects the cake's texture and moisture. When mixed with boiling water, it enhances the cocoa's flavor and makes the batter smoother, contributing to a moist and tender crumb once baked.

Using granulated sugar in this recipe serves more than just sweetness. It helps to keep the cake moist by interacting with the liquid ingredients. If you want a slightly richer flavor, consider substituting part of the granulated sugar with brown sugar, which will also add a hint of caramel undertones to your cake.

Perfecting the Baking Process

Baking times can vary depending on your oven, so it's crucial to keep an eye on your chocolate sheet cake as it bakes. I suggest checking for doneness a couple of minutes before the 20-minute mark by inserting a toothpick in the center. If it comes out with moist crumbs, it's perfect; if it has wet batter, give it a few more minutes. Be careful not to overbake, as that can lead to a dry cake, which we want to avoid.

Cooling the cake completely before frosting is vital. If you frost a warm cake, the frosting may melt and slide off, ruining the aesthetic and texture. Allow it to sit in the pan for about 10-15 minutes before transferring it to a wire rack. This ensures even cooling and helps to prevent any sogginess from the bottom.

Ingredients

For the Cake

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

For the Frosting

1/2 cup unsalted butter, softened
2/3 cup 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) and grease a sheet cake pan.

Mix Dry Ingredients

In a large bowl, whisk together flour, sugar, cocoa powder, baking soda, baking powder, and salt.

Combine Wet Ingredients

In another bowl, beat together the eggs, milk, oil, and vanilla extract.

Combine and Add Water

Pour the wet ingredients into the dry ingredients and mix well. Gradually stir in the boiling water until smooth.

Bake

Pour the batter into the prepared pan and bake for 20 minutes or until a toothpick comes out clean.

Prepare the Frosting

While the cake is cooling, prepare the frosting by creaming the butter and cocoa together, then gradually add powdered sugar and milk until smooth.

Frost the Cake

Once the cake has completely cooled, frost it with your buttercream frosting and enjoy!

Pro Tips

For an extra touch, consider adding chocolate shavings or sprinkles on top of the frosting before serving.

Frosting Techniques

For the frosting, it's important to cream the butter properly until it's light and fluffy before adding cocoa and sugar. This aeration creates a lighter texture in the frosting, making it easy to spread. I recommend using room-temperature butter to facilitate this process—cold butter can lead to a heavy frosting that clumps rather than spreads smoothly.

If you find your frosting is too thick, add more milk, one tablespoon at a time, until you reach your desired consistency. Conversely, if the frosting is too runny, gradually add more powdered sugar. This flexibility allows you to adjust the icing to your preference, ensuring it complements the cake perfectly.

Serving Suggestions

This chocolate sheet cake can be served as is for a classic approach, or consider adding a touch of elegance with fresh berries and whipped cream on the side. This adds a delightful contrast in flavor and texture. I love adding orange zest to the cake or frosting to elevate the chocolate flavor and provide a bright finish that enhances the overall experience.

For a more indulgent twist, you could layer this cake with ganache or serve it warm with a scoop of vanilla ice cream on top. This not only adds a rich creaminess but also a delightful contrast to the soft, moist cake. It makes for a memorable dessert, sure to impress any guest!

Questions About Recipes

→ Can I use a different frosting?

Absolutely! Feel free to try cream cheese frosting or a ganache for a unique twist.

→ How should I store the cake?

Store your chocolate sheet cake in an airtight container at room temperature for up to 3 days.

→ Can I freeze the cake?

Yes! You can freeze the unfrosted cake for up to 3 months; just wrap it tightly in plastic wrap.

→ What can I use instead of eggs?

You can substitute eggs with applesauce or flaxseed meal mixed with water for a vegan option.