Chocolate Sheet Cake With Frosting

Name: Chocolate Sheet Cake With Frosting
Prep time: 20 min
Cook time: 30 min
Total time: 50 min
Yield: 12 servings
Ingredients: 2 cups all-purpose flour; 1 3/4 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 whole milk; 1/2 cup vegetable oil; 2 teaspoons vanilla extract; 1 cup boiling water; 1/2 cup unsalted butter, softened; 2/3 cup unsweetened cocoa powder; 3 cups powdered sugar; 1/3 cup whole milk; 1 teaspoon vanilla extract

Highlighted under: Sweet Collection

I absolutely love making this chocolate sheet cake with frosting—it never fails to impress! The decadent chocolate flavor pairs perfectly with a rich, creamy frosting that I could eat by the spoonful. We often make it for special celebrations, but I find myself craving it on regular days, too. This recipe is incredibly simple and can be whipped up in just a short time, making it an easy go-to for both novice and experienced bakers alike. You’ll want to savor every bite of this irresistible treat!

Created by

Elodie March

Last updated on 2026-01-24T09:49:35.198Z

When I first attempted to make chocolate sheet cake, I was amazed at how quickly the batter came together. I remember mixing the ingredients in one bowl, which made cleanup a breeze and was a game changer for my busy mornings. The end result was a moist cake that was simple yet incredibly satisfying. In fact, I often double the recipe and keep an extra cake in the freezer for unexpected guests!

The frosting is just as easy and might just be the star of the show. Using cocoa powder and butter gives it a lovely texture that smooths out beautifully when spread over the cake. I've learned to let the cake cool completely before frosting to ensure that it sets nicely. Trust me—it’s worth the wait!

Why You'll Love This Recipe
Moist and rich chocolate flavor that's hard to resist
Simple one-bowl preparation for easy cleanup
Perfect for spontaneous celebrations or casual gatherings

Baking Technique for Perfect Texture

Achieving the perfect texture in your chocolate sheet cake hinges on how you mix your ingredients. It's crucial to combine the dry ingredients thoroughly before adding wet ones. If you accidentally skip this step, you could end up with clumps of cocoa or flour that won't dissolve properly. Remember to mix just until you see no dry flour remaining; overmixing could lead to a dense cake.

When boiling the water to add to your batter, I recommend using a pot or kettle to ensure the water reaches a rolling boil. This hot water helps to bloom the cocoa, intensifying your chocolate flavor. It can also help to create a lighter cake, so don't skip this step! Your batter should be quite thin—this is normal and contributes to that moist texture.

Frosting Tips for the Smoothest Finish

The secret to a beautifully smooth frosting lies in the temperature of your butter. Make sure it's softened but not melted; it should yield slightly when pressed with a finger. If the butter is too soft, you risk ending up with a runny frosting that won't hold its shape on the cake. Beat it just until creamy and then gradually add the cocoa and sugar while mixing on low speed to prevent a sugar cloud.

If you find your frosting too thick after adding in the powdered sugar, simply whisk in more milk—a tablespoon at a time—until it reaches your desired consistency. Watching for a glossy finish while mixing helps ensure your frosting is light and spreadable. This level of attention makes for a perfect frosting that’s rich and creamy without being weighted down.

Creative Serving Suggestions

While the chocolate sheet cake is delicious on its own, I love to serve it with a scoop of vanilla ice cream or a dollop of whipped cream for an indulgent dessert experience. The cold, creamy contrast complements the rich cake perfectly. You can also garnish with fresh berries or a sprinkle of sea salt to enhance the flavors without overpowering the chocolate.

For a fun twist, consider adding a flavored syrup drizzled on top or even some crushed nuts for texture. Chopped hazelnuts or pecans add a delightful crunch that contrasts beautifully with the cake’s moistness. You can also experiment by including an element of surprise, such as filling the cake with chocolate ganache or fruit preserves before frosting it.

Ingredients

For the Cake

2 cups all-purpose flour
1 3/4 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 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 unsweetened cocoa powder
3 cups powdered sugar
1/3 cup whole milk
1 teaspoon vanilla extract

Instructions

Prepare the Cake

Preheat your oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan. In a large bowl, combine flour, sugar, cocoa powder, baking soda, baking powder, and salt. Mix on low speed until well combined.

Combine Wet Ingredients

Add eggs, milk, oil, and vanilla to the dry ingredients. Mix on medium speed until smooth. Gradually stir in boiling water until fully combined—this will make the batter thin.

Bake the Cake

Pour the batter into the prepared pan and bake for 30-35 minutes or until a toothpick inserted in the center comes out clean. Let it cool completely in the pan.

Make the Frosting

In a bowl, beat the softened butter until creamy. Gradually add cocoa powder and then the powdered sugar, alternating with milk, mixing until smooth. Stir in the vanilla extract.

Frost the Cake

Once the cake is completely cooled, spread the frosting evenly on top using a spatula. Cut into squares and serve.

Pro Tips

For an extra chocolatey flavor, consider adding chocolate chips to the batter or a pinch of espresso powder to the frosting.

Storage and Freezing Guidelines

To keep your chocolate sheet cake fresh, store it covered at room temperature for up to four days. If you need to store it longer, you can wrap individual pieces in plastic wrap and place them in an airtight container in the freezer for up to three months. When you're ready to enjoy, simply let it thaw at room temperature for a couple of hours.

If your frosting is still intact on the cake, you can cover it with a cake dome or similar cover to maintain moisture. If your cake develops a crust on the frosting after a day or two, giving it a quick spritz with water before serving can help rejuvenate the texture.

Adjusting for Dietary Needs

If you're looking for a gluten-free version of this chocolate sheet cake, consider using a one-to-one gluten-free flour blend. Check that your cocoa powder is also gluten-free, as some brands could contain traces. The moisture content from the boiling water makes it accommodating for gluten-free flour, which can sometimes result in drier cakes with other recipes.

For a dairy-free option, substitute whole milk with almond milk or another non-dairy alternative. Make sure to use a vegan butter substitute in the frosting, such as coconut oil or any plant-based butter. The flavor profile will remain rich and chocolaty while accommodating different dietary preferences.

Scaling the Recipe

This recipe scales well if you want to make a larger batch. To make a double layer cake, simply double all the ingredients and divide the batter between two 9-inch round cake pans. You will still bake at 350°F (175°C), but keep an eye on the bake time; it may take an additional 5–10 minutes, so use the toothpick test to ensure they are done.

Conversely, if you want to make a smaller batch, you can easily halve the ingredients and use an 8x8 inch pan. Bake for about 25–30 minutes, checking for doneness. This flexibility makes it easy to enjoy this chocolate treat whether for a large gathering or a simple family night.

Questions About Recipes

→ Can I use a different type of milk?

Yes, you can use almond milk, soy milk, or coconut milk as substitutes.

→ How long does the cake last?

The cake can be stored in an airtight container at room temperature for up to 3 days, or it can be refrigerated for a week.

→ Can I freeze the cake?

Absolutely! Just make sure it’s completely cooled and wrapped tightly in plastic wrap before freezing.

→ Is there a vegan option for the cake?

Yes! You can replace the eggs with flax eggs and use plant-based milk and oil as substitutes.