This easy chocolate sheet cake is moist, fudgy, and far better than any box mix. Top it with chocolate buttercream, your favorite frosting, or a scoop of ice cream. Made with simple pantry ingredients and baked in a 9×13 inch pan, it’s perfect for birthdays, potlucks, or whenever you want an uncomplicated chocolate cake.
This post was updated August 20, 2024 with a slightly revised recipe, tips, and photos
Everyone should have a reliable, easy chocolate cake in their recipe box, and this chocolate sheet cake fits the bill. It has a balanced chocolate flavor—not too heavy—yet very moist and fudgy. Properly stored, it stays fresh for up to four days.
I like to spread a thick layer of chocolate frosting on top for extra indulgence, but it’s also delicious with vanilla frosting, peanut butter buttercream, or Oreo frosting. If you prefer not to frost, serve warm slices with ice cream, whipped cream, or fresh berries.
The best part is how simple the ingredients and steps are. This recipe uses pantry staples—oil, cocoa powder, milk, and a bit of sour cream or Greek yogurt—so you probably won’t need a trip to the store.
Chocolate Sheet Cake Recipe
This cake is quick to prepare—the batter comes together in under 10 minutes and then bakes. Here’s an overview of the method.
- Preheat the oven to 350°F (180°C) and prepare a 9×13-inch pan. For a classic chocolate finish, lightly grease and dust the pan with cocoa powder. If you plan to lift the cake from the pan after baking or freeze it, line the pan with parchment paper with an overhang for easy removal.
- In a large bowl, whisk together the dry ingredients: flour, sugar, cocoa powder, baking soda, baking powder, and salt. If your cocoa is lumpy, sift it first for a smooth batter.
- In a separate bowl, whisk the wet ingredients: vegetable oil, milk, sour cream (or plain Greek yogurt), eggs, and vanilla extract.
- Make a well in the dry ingredients and pour the wet mixture into the center. Stir gently at first with a rubber spatula, then whisk until about 75% combined.
- When the batter is mostly combined, add the hot coffee (or boiling water) and whisk until smooth. The hot liquid helps the cocoa bloom, intensifying the chocolate flavor and giving the cake a richer taste.
- Pour the batter into the prepared pan and bake for 35–40 minutes, checking around 30 minutes. The cake is done when the top is set and a toothpick inserted in the center comes out clean or with a few moist crumbs—there should be no wet batter on the toothpick.
For the Chocolate Frosting
The frosting is a classic chocolate buttercream made with unsalted butter, powdered sugar, cocoa powder, cream or milk, a bit of vanilla, and a pinch of salt. Beat the butter until softened, then add sifted powdered sugar and cocoa, starting on low speed and increasing to medium. Add cream or milk a tablespoon at a time until you reach a fluffy, spreadable consistency.
Make sure the cake is fully cooled before frosting. If you’re short on time or prefer less frosting, warm slices with ice cream or whipped cream are a lovely alternative.
Freezing Instructions
Sheet cakes freeze well. Once cooled:
- Invert the pan onto a flat surface (cardboard, cutting board, or cookie sheet). Lining the pan with parchment before baking makes removal easier if you plan to freeze.
- Wrap the entire cake tightly in plastic wrap, pressing it close to the surface to prevent freezer burn. Wrap multiple times if necessary.
- Cover the wrapped cake with aluminum foil and place it on a flat surface in the freezer for up to three months.
- Thaw overnight in the refrigerator, then bring to room temperature before decorating.
Frosted cakes can be frozen, but results are generally better when freezing unfrosted cake and applying frosting after thawing.
How Many People Does a Sheet Cake Serve?
A 9×13 inch sheet cake yields about 18 medium slices (2×3 inches) or roughly 29 smaller pieces (2×2 inches), depending on how you cut it.
Below are the ingredient groups and the main instructions as used in the original recipe:
Chocolate Sheet Cake
Equipment
- 9×13 inch (23 x 33 cm) baking pan
Ingredients
Chocolate Sheet Cake
- 2 cups all-purpose flour (250 g)
- 1/2 cup cocoa powder (45 g)
- 2 cups granulated sugar (400 g) — use 1 3/4 cups for a slightly less sweet cake
- 2 teaspoons baking soda
- 1/2 teaspoon baking powder
- 1/4 teaspoon salt
- 1/2 cup vegetable oil (120 ml)
- 2 large eggs
- 2 teaspoons vanilla extract
- 1/2 cup milk (120 ml) — whole milk preferred
- 1/2 cup sour cream (120 ml) or plain Greek yogurt
- 3/4 cup hot brewed coffee (180 ml) or boiling water
Chocolate Frosting
- 3/4 cup unsalted butter (168 g), softened
- 3–4 cups powdered sugar (330–440 g), sifted
- 1/2 cup cocoa powder (45 g), sifted
- 1 teaspoon vanilla extract
- 1/4 teaspoon salt
- 4–5 tablespoons whipping cream or milk (60–75 ml), as needed
Instructions
Chocolate Sheet Cake
- Preheat the oven to 350°F (180°C) and prepare the pan as described above.
- Whisk together flour, cocoa, sugar, baking soda, baking powder, and salt. Sift the cocoa if needed.
- In a separate bowl, whisk oil, vanilla, eggs, milk, and sour cream.
- Make a well in the dry ingredients and add the wet mixture. Stir gently to combine, then whisk until about three-quarters combined.
- Pour in the hot coffee and whisk vigorously until the batter is smooth and even, about one minute.
- Pour batter into the prepared pan and bake 35–40 minutes, checking around 30 minutes. A toothpick should come out clean or with a few moist crumbs.
Chocolate Frosting
- Beat the softened butter until smooth.
- Sift in 2 cups of powdered sugar and the sifted cocoa, add vanilla and salt, and mix starting on low speed and increasing to medium.
- Add remaining powdered sugar in 1/2 cup increments, alternating with 1–2 tablespoons of cream until you reach the desired consistency and sweetness.
- Ensure the cake is completely cool before spreading the frosting with a flat knife. Decorate as desired.
Notes
- Cocoa: Dutch-process (specialty dark) cocoa gives the best flavor.
- Room Temperature: Use room-temperature eggs, milk, and sour cream for a smoother batter.
- Sour Cream: Plain Greek yogurt can replace sour cream. Avoid flavored yogurts.
- Hot Coffee: Coffee deepens the chocolate flavor; boiling water may be used as an alternative.
- Storage: Unfrosted cake can be covered at room temperature overnight. Frosted cake is fine at room temperature for up to 8 hours, then store covered in the fridge for up to 4 days. Allow chilled cake to sit 30 minutes at room temperature before serving.
- Nutrition: Nutrition details are estimates based on one slice of cake with frosting (18 servings).
Nutrition
Enjoy this simple, crowd-pleasing chocolate sheet cake—easy to make, reliably delicious, and ideal for any occasion.