This Perfect Chocolate Sheet Cake is rich, moist, and deeply chocolatey with a soft, tender crumb and a silky chocolate buttercream on top. Baked in a 9×13-inch pan, it’s an easy, no-fuss dessert that’s perfect for birthdays, potlucks, or anytime you need a reliable chocolate cake that feeds a crowd. If you’re in the mood for vanilla, try my Best White Sheet Cake, too!

Ingredients & Substitutions
- All-purpose flour: I used all-purpose flour for structure and a soft crumb. It keeps the cake sturdy enough for a 9×13 pan while still staying tender. You can use a 1:1 gluten-free flour if needed, though the texture may vary slightly.
- Granulated sugar: Sweetens the cake and helps keep it moist. It also works with the eggs to create a soft, tender texture.
- Cocoa powder: Use a good-quality unsweetened cocoa powder for the best flavor. This is where most of the chocolate taste comes from, so it’s worth using one you like.
- Baking soda & baking powder: These work together to help the cake rise properly and stay light instead of dense.
- Buttermilk: Adds moisture and a slight tang that keeps the cake from tasting too sweet. If you don’t have buttermilk, you can use milk mixed with 1 tablespoon of vinegar or lemon juice.
- Vegetable oil: Keeps the cake soft and moist, even after it cools. Canola oil works just as well.
- Eggs: Add structure and richness. Room temperature eggs mix more evenly into the batter.
- Hot coffee (or hot water): Hot liquid helps bloom the cocoa powder for a deeper chocolate flavor. Coffee won’t make the cake taste like coffee; it just makes the chocolate richer. I use it in some of my other favorite chocolate desserts, like my ultimate chocolate cupcakes and perfect chocolate cake, just to name a couple! But hot water works if preferred, or if you don’t have coffee.
- Chocolate Buttercream: This is a rich, fluffy buttercream made by whipping butter and confectioners’ sugar until light, then blending in cocoa powder, vanilla, heavy cream, and a pinch of salt. It whips up smooth and airy, making it easy to spread over the cake.

FAQs
Can I use hot water instead of coffee?
Yes! Hot water works just fine. But coffee enhances the chocolate flavor without making the cake taste like coffee.
Can I make this chocolate sheet cake ahead of time?
Yes. You can bake the cake a day in advance and frost it the next day. Keep it covered at room temperature.
Can I add chocolate chips or nuts?
Yes, you can fold in about 1/2 to 1 cup of chocolate chips or chopped nuts if you’d like a little extra texture. Just keep in mind the cake will be a bit denser.
Can I use a different frosting?
Absolutely. Whipped cream cheese frosting or a simple chocolate ganache would both work well here.
Can I use a different pan size?
This recipe is best for a 9×13-inch pan. If using a different size, the bake time will need to be adjusted.

Serving Ideas
- Serve with a scoop of no-churn vanilla ice cream (or your favorite no-churn ice cream recipe!) for a simple, classic dessert.
- Add fresh berries on the side to balance the richness.
- Enjoy with a glass of cold milk or a cup of coffee.
- Warm a slice for a few seconds for an extra soft, fudgy texture.

How to Store Chocolate Sheet Cake
Room Temperature: Store the frosted cake covered for up to 2 days. Keeping it covered helps prevent it from drying out.
Refrigerator: For longer storage, cover and refrigerate for up to 5 days. Let slices come to room temperature before serving for the best texture.
Freezer: You can freeze the cake, frosted or unfrosted, for up to 2 months. Wrap tightly in plastic wrap, then foil. Thaw overnight in the refrigerator and bring to room temperature before serving.

Perfect Chocolate Sheet Cake
Ingredients
Cake
- 1 ¾ cups (219 g) all-purpose flour
- 2 cups (400 g) granulated sugar
- ¾ cup (90 g) unsweetened cocoa powder
- 2 teaspoons baking soda
- 1 teaspoon baking powder
- 1 teaspoon kosher salt
- 1 cup (240 g) buttermilk, room temperature
- ½ cup (112 g) vegetable oil
- 2 large eggs, room temperature
- 2 teaspoons pure vanilla extract
- 1 cup (237 g) freshly brewed hot coffee, or hot water
Chocolate Buttercream Frosting
- 1 ½ cups (3 sticks / 340 g) unsalted butter, room temperature
- 4 cups (500 g) confectioners' sugar
- ¾ cup (88.5 g) cocoa powder
- 2 teaspoons vanilla extract
- 1 pinch table salt
- 4 tablespoons heavy whipping cream
Instructions
Cake
- Preheat oven to 350°F. Spray a 9×13-inch baking dish with nonstick cooking spray. Set aside.
- In the bowl of a stand mixer, add flour, sugar, cocoa powder, baking soda, baking powder, and salt. Mix to combine.
- In a separate bowl, whisk buttermilk, oil, eggs, and vanilla.
- With mixer on low, slowly add wet ingredients to dry.
- Add hot coffee (or water) and mix just until combined, scraping the bowl as needed.
- Pour batter into the prepared pan. Tap pan on the counter to remove air bubbles.
- Bake 28 to 32 minutes, or until a toothpick inserted in the center comes out with moist crumbs (no wet batter). Start checking at 28 minutes to avoid overbaking.
- Let the cake cool completely in the pan on a wire rack.
Chocolate Buttercream
- In the bowl of a stand mixer fitted with whisk attachment, whisk butter and sugar on medium-high speed until very pale and fluffy or about five minutes. Be sure to stop at least once and scrape the bowl.
- With the mixer off, add in cocoa powder, vanilla and salt.
- Turn mixer on low and blend for about 30 seconds.
- One tablespoon at a time add in heavy cream.
- Once all cream has been added and mixture is mostly combined, turn off the mixer and scrape down the sides of the bowl.
- Now turn the mixer onto medium-high to high and whisk for 3 to 5 minutes or until mixture is lighter and fluffier. The frosting will be shiny and seem to have many large air bubbles throughout and this is exactly what we are going for. (You can smooth those out on the cake if so desired.)
- Generously frost the cooled cake with chocolate buttercream* (or your favorite topping).
Notes
Did you make this recipe?
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