Chocolate Ganache Sheet Cake

Name: Chocolate Ganache Sheet Cake
Prep time: 20 min
Cook time: 30 min
Total time: 50 min
Yield: Serves 12
Ingredients: 1 ¾ cups all-purpose flour; 1 ¾ cups granulated sugar; ¾ cup unsweetened cocoa powder; 1 ½ teaspoons baking powder; 1 ½ teaspoons baking soda; 1 teaspoon salt; 2 large eggs; 1 cup whole milk; ½ cup vegetable oil; 2 teaspoons vanilla extract; 1 cup boiling water; 1 cup heavy cream; 8 ounces semisweet chocolate, chopped; 1 tablespoon butter (optional)

Highlighted under: Homemade Baking Collection

I absolutely love making a Chocolate Ganache Sheet Cake for any gathering. The combination of rich chocolate cake soaked in velvety ganache truly creates a dessert that everyone adores. With just a few simple ingredients and straightforward steps, I've managed to simplify this beloved treat without sacrificing any flavor. The best part? It's perfect for serving a crowd, and I can customize it easily with various toppings or flavors if I desire.

Created by

Rosamund Blake

Last updated on 2026-02-16T04:01:35.552Z

When I first made a Chocolate Ganache Sheet Cake, I was pleasantly surprised by how easy it was to get delicious results. The secret lies in using quality cocoa powder and letting the ganache set properly before pouring it over the cake. Each slice becomes a decadent experience, with moist cocoa layers and a glossy chocolate finish that elevates the entire dessert.

After numerous attempts, I've discovered that allowing the cake to cool completely before adding the ganache makes a huge difference. Not only does it help the ganache adhere better, but it also intensifies the flavors, leaving everyone wanting more. I've even experimented with adding a hint of espresso powder to the ganache, which adds a delightful depth!

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

Mastering Ganache Texture

Making a smooth and glossy ganache is all about patience and the right temperature. When heating the heavy cream, avoid boiling it aggressively; you want it to simmer gently. This helps to emulsify the chocolate once added, resulting in a silky finish. If you find the ganache too thick after cooling, simply warm it up and stir in a bit more cream to achieve your desired consistency.

For an alternative ganache, consider using different types of chocolate. Dark chocolate provides a rich and intense flavor, while milk chocolate offers a sweeter profile. If you're looking for a lower-sugar option, semi-sweet chocolate or even a sugar-free chocolate substitute can work well. Just keep in mind that the ganache's texture may vary slightly, so adjust the cream ratio as needed.

Cake Storage and Serving Tips

Once your Chocolate Ganache Sheet Cake has cooled and the ganache has set, you can store it covered at room temperature for up to three days. For longer storage, refrigerate the cake; just remember to bring it back to room temperature before serving to enhance its flavors. If you're preparing it in advance, the cake itself can last several days unfrosted, allowing you to make it ahead of time.

For a delightful serving suggestion, I love adding fresh orange zest to the ganache just before pouring it over the cake. This citrus addition brightens the deep chocolate flavor and adds an unexpected but pleasant contrast. Alternatively, top with fresh berries or crushed nuts for texture, providing an appealing visual and textural element on each slice.

Ingredients

Gather the following ingredients to create this delicious cake.

For the Cake

1 ¾ cups all-purpose flour
1 ¾ cups granulated sugar
¾ cup unsweetened cocoa powder
1 ½ teaspoons baking powder
1 ½ teaspoons baking soda
1 teaspoon salt
2 large eggs
1 cup whole milk
½ cup vegetable oil
2 teaspoons vanilla extract
1 cup boiling water

For the Ganache

1 cup heavy cream
8 ounces semisweet chocolate, chopped
1 tablespoon butter (optional)

Mix the ingredients thoroughly to ensure a scrumptious result!

Instructions

Follow these steps to create your Chocolate Ganache Sheet Cake.

Prepare the Cake

Preheat your oven to 350°F (175°C) and grease a sheet pan. In a large mixing bowl, combine flour, sugar, cocoa powder, baking powder, baking soda, and salt. Add eggs, milk, oil, and vanilla, then mix well until smooth. Stir in boiling water slowly. Pour the batter into the prepared pan.

Bake

Bake in the preheated oven for 30 minutes or until a toothpick inserted in the center comes out clean. Let the cake cool completely in the pan on a wire rack.

Make Ganache

In a small saucepan, heat the heavy cream until it begins to simmer. Remove from heat and add the chopped chocolate. Let it sit for a few minutes, then stir until smooth. Optionally, add butter for a glossy finish.

Finish the Cake

Once the cake is cool, pour the ganache evenly over the top, allowing it to drip down the sides. Let it set before slicing.

Once finished, serve and enjoy this delectable cake!

Pro Tips

For added flavor, consider infusing your ganache with vanilla extract or a splash of liqueur. Additionally, topping the cake with fresh berries adds a delightful contrast to the rich chocolate.

Ingredient Importance

The use of boiling water in the cake batter may seem unusual, but it's a key step for ensuring a moist and tender cake. This method blooms the cocoa powder, intensifying its flavor and giving the cake a rich chocolate color. Don’t skip this step—using warm or cold water will result in a denser texture and less flavorful cake.

Vegetable oil is preferred over butter in this cake recipe because it contributes to a softer crumb. Oil remains liquid at room temperature, keeping the cake moist for longer. You can substitute the vegetable oil for other neutral oils, like canola or grapeseed, if needed, but avoid strongly flavored oils that might alter the cake’s taste.

Baking Tips and Tricks

To achieve even baking, ensure your oven is preheated fully before placing the cake inside. An oven thermometer can help you verify that the correct temperature is reached, as many ovens can be off by 10-15°F. Additionally, place your cake pan in the center of the oven for optimal heat distribution.

When it comes to checking if your cake is done, a toothpick inserted in the center should come out clean or with just a few moist crumbs attached. If it comes out with wet batter, return it to the oven for a few extra minutes, checking again after three to five minutes. Be careful not to overbake, as that can lead to dryness.

Questions About Recipes

→ Can I make this cake in advance?

Yes, you can bake the cake a day ahead and store it tightly wrapped at room temperature. Just add the ganache on the day you plan to serve it.

→ Can I freeze the Chocolate Ganache Sheet Cake?

Absolutely! Once fully cooled and ganache has set, you can freeze slices in an airtight container for up to three months.

→ What type of chocolate should I use for the ganache?

I recommend using a good quality semisweet or dark chocolate for a rich flavor. Milk chocolate can also work for a sweeter ganache.

→ Can I substitute ingredients?

Definitely! You can use almond or oat milk instead of whole milk, and coconut oil instead of vegetable oil for a dairy-free option.