Moist Chocolate Sheet Cake With Chocolate Frosting

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

Highlighted under: Sweet Tooth Favorites

I absolutely love baking, and this Moist Chocolate Sheet Cake With Chocolate Frosting is one of my top go-to recipes. The combination of rich cocoa and the perfect amount of moisture makes this cake an absolute delight. I find that using high-quality cocoa powder really enhances the flavor, and topping it off with a silky chocolate frosting makes it utterly irresistible. Whether for a special occasion or just because, this cake never disappoints and brings joy to everyone who tries it.

Created by

Phoebe Turner

Last updated on 2026-03-05T06:45:53.855Z

When I first attempted this cake, I was trying to recreate a childhood favorite that I used to enjoy at family gatherings. After experimenting with different methods and ingredients, I discovered that using buttermilk adds a level of tenderness that truly makes this cake stand out. It's moist yet holds together beautifully, making it perfect for layering or serving as is.

The frosting is where I learned the magic of melted chocolate combined with butter and powdered sugar. It transforms into a rich and fluffy topping that complements the cake perfectly. I recommend letting it sit for a bit to thicken before spreading for the best results!

Why You Will Love This Recipe
Rich chocolate flavor that satisfies every sweet tooth
Incredibly moist texture that keeps it fresh for days
Easy to make and perfect for any occasion

Mastering Moisture in Your Cake

Achieving the ideal moistness in a chocolate sheet cake relies heavily on the balance of liquid ingredients. The buttermilk and vegetable oil contribute to a tender crumb, while the boiling water amplifies the cocoa's flavor and moisture content. If you find you're out of buttermilk, plain yogurt or milk with a splash of vinegar works as a great substitute, maintaining the cake's necessary acidity for leavening.

Another key factor to consider is mixing time. Once you add your wet ingredients to the dry, mix only until just combined to avoid overworking the gluten in the flour. This method will help ensure that your cake has a light, tender texture instead of a dense one, which can be a common pitfall of chocolate cakes.

Frosting Finesse

When preparing the chocolate frosting, it's crucial to beat the softened butter until creamy and fluffy. This aeration helps create a light and spreadable texture in your frosting. If your frosting seems too thick, a teaspoon or two of extra milk can help achieve that perfect consistency without compromising the flavor.

For a richer chocolate flavor, consider adding a touch more cocoa powder than the recipe calls for, but be cautious—too much can alter the balance. To prevent any graininess, ensure you sift the cocoa powder before mixing it in, helping it dissolve better into the butter and sugar.

Ingredients

Gather your ingredients before you start baking to ensure a smooth process.

Cake Ingredients

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

Frosting Ingredients

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

Make sure you measure all the ingredients accurately for the best results!

Instructions

Preheat your oven and prepare your baking pan before you start mixing.

Prepare Your Pan

Preheat your oven to 350°F (175°C). Grease and flour a 9x13-inch baking pan.

Mix Dry Ingredients

In a large mixing bowl, combine flour, sugar, cocoa powder, baking powder, baking soda, and salt.

Add Wet Ingredients

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

Incorporate Boiling Water

Carefully stir in the boiling water. The batter will be thin, but that’s how it should be.

Bake the Cake

Pour the batter into the prepared pan and bake for 30 minutes, or until a toothpick comes out clean.

Make the Frosting

In a medium bowl, beat the butter until creamy. Gradually add cocoa powder, powdered sugar, milk, and vanilla, beating until smooth.

Frost the Cake

Allow the cake to cool completely before frosting. Spread the frosting evenly over the top.

Serve and Enjoy

Slice and serve your delicious chocolate sheet cake to friends and family!

Enjoy your delicious creation with a cup of coffee or tea!

Pro Tips

Using room temperature ingredients can help make your cake lighter and fluffier. Don't skip the boiling water step
it makes a huge difference in the cake's moisture content!

Storing and Serving

This chocolate sheet cake is perfect for make-ahead servings. Once completely cooled, it can be stored in an airtight container at room temperature for up to three days or in the refrigerator for a week. If you wish to freeze it, slice the cake first, wrap individual pieces in plastic wrap, and store them in a freezer-safe bag. It will hold well for up to three months; just let it thaw overnight in the fridge before serving.

For serving, you can dress up the cake with fresh berries, a sprinkle of sea salt, or even a drizzle of caramel sauce to complement the rich chocolate flavor. Pair it with a scoop of vanilla ice cream for an elevated dessert experience that balances the cake's richness with creamy sweetness.

Common Troubleshooting Tips

If your cake sinks in the middle, it usually means it was underbaked. A toothpick inserted into the center should come out clean or with a few moist crumbs, not wet batter. Always check your cake a couple of minutes before the suggested baking time, as oven temperatures can vary. If you find that your cake tends to stick to the pan, ensure it's well-greased and floured, or use parchment paper for extra insurance.

If you notice your frosting is too sweet, a touch of salt can help balance the flavors and make the chocolate taste more pronounced. Similarly, if it turns out too thin, catch it before the final spread: refrigerate for about 15 minutes and re-whip to achieve the perfect spreadable texture.

Questions About Recipes

→ Can I substitute buttermilk with regular milk?

Yes, you can use regular milk, but for the best texture, consider adding a tablespoon of vinegar or lemon juice to sour the milk.

→ How do I store leftover cake?

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

→ Can I freeze the cake?

Absolutely! Wrap the frosted or unfrosted cake in plastic wrap and freeze for up to 3 months. Thaw in the refrigerator before serving.

→ What can I use for decorations?

You can use chocolate shavings, sprinkles, or fresh berries to add a decorative touch on top of the frosting.