Best Chocolate Cake Recipe (9×13 Recipe)
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An easy, rich 9×13 Chocolate Cake Recipe made in one bowl with minimal ingredients. Based on my popular best chocolate cake recipe, it is tender, moist, and delicious!
This is the easiest 9×13 chocolate cake recipe I’ve ever made. From my Best Chocolate Cake that everyone loves, I’ve made the cake even easier and sized for a 9×13 sheet cake!
I love this easy 9×13 size cake for taking to potlucks, tailgating, baking, taking to friends or neighbors, and for making a quick and easy cake! It transports beautifully in the baking dish and I love that I don’t have to worry about a cake slipping or sliding on a cake plate! Another favorite version you may enjoy is my Chocolate Loaf Cake. So easy!
I originally shared this recipe in 2014 and have updated it to include the metric conversion to grams as well as updated the recipe sizing to make for a thicker cake based on reader feedback.
Best Chocolate Cake (9×13 Recipe)
What Makes a Chocolate Cake Moist?
This cake recipe includes the perfect ratio of oil, milk, and boiling water to make it moist without having to use melted chocolate. The combination of the fat, protein, and water temperature produces a moist and tender crumb.
Ingredients for Easy 9×13 Chocolate Cake
Be sure to see the recipe card below for the full listing of ingredients, instructions, notes, and estimated nutritional information.
- all-purpose flour – I recommend using a good quality all-purpose flour that works well in baking. You can also substitute with cake flour if needed.
- sugar – You’ll use granulated sugar.
- unsweetened cocoa powder – I use unsweetened cocoa powder.
- baking powder – used to leaven the cake.
- baking soda – also used to help the cake rise.
- kosher salt – I use Diamond Crystal Kosher Salt. If you substitute with Morton’s Kosher salt, fine sea salt, or table salt, you will only need half the amount of the salt called for in the recipe.
- espresso powder – Espresso powder enhances the flavor of chocolate in recipes. The amount used in this cake does not give a coffee flavor to the cake or leave a bitter aftertaste that you may get from using brewed coffee or instant coffee in the cake batter. You can use homemade espresso powder or your favorite store-bought. Many grocery stores now carry it. You can also omit it if you prefer or are unable to find it.
- milk – You can use buttermilk, whole milk, or coconut milk.
- vegetable oil – the oil is key for a moist chocolate cake.
- egg – Make sure that your egg is at room temperature so that it combines more easily into the cake batter.
- vanilla extract – Use good quality vanilla extract.
- boiling water – helps release the chocolate flavor in the recipe. Please don’t skip it!
Chocolate Buttercream
I scaled the chocolate buttercream frosting to work perfectly in a 9×13 baking dish. The cake still rises nicely so that you have a lovely, thick cake that you then top with a generous amount of silky chocolate buttercream.
Chocolate Buttercream Ingredients: you’ll need butter, cocoa powder, confectioner’s sugar, milk, vanilla extract, and espresso powder.
Step-by-Step Instructions
Prep. Preheat the oven and prep the baking dish.
Make the cake batter. Add the flour, sugar, cocoa powder, baking powder, baking soda, salt, and espresso powder to a large mixing bowl. Whisk through to combine. Add the milk, oil, eggs, and vanilla extract to the flour mixture and combine. Carefully stir in the boiling water until well combined. The cake batter will be thin.
Bake the cake. Pour the cake batter into the prepared 9×13 baking dish. Bake for 30 to 40 minutes, until a toothpick inserted in the center comes out clean. Remove from the oven and cool the baking dish on a wire rack until cooled completely.
Make the frosting. Meanwhile, add cocoa powder to a large mixing bowl. Whisk to break up any large lumps in the cocoa powder. Add the butter and using a hand mixer, cream the butter and cocoa powder together until well combined. Add confectioner’s sugar to another large bowl and whisk through it. Add the confectioner’s sugar and milk to the cocoa mixture by adding 1 cup of confectioner’s sugar followed by about a tablespoon of milk. After combining each addition, turn the mixer onto a high speed for about a minute. Repeat until all sugar and milk have been added. Add vanilla extract and espresso powder and combine well. Mix until the frosting is silky and smooth.
I put together a quick video to show you just how easy the cake is to mix together. Seriously, it’s the easiest and most delicious cake ever, I think! 🙂
As with any 9×13 cake recipe, you can cut the pieces as generously or as conservatively as you please. You can cut the cake into 2-inch x 2-inch pieces for 24 servings or 2-inch x 3-inch pieces for 18 servings.
Here’s my Easy 9×13 Chocolate Cake Recipe. I think you are going to love how simple it is!
Best Chocolate Cake Recipe (9×13 Recipe)
Ingredients
Chocolate Cake Recipe (9×13 Recipe)
- 2 cups (240 g) all-purpose flour
- 2 cups (396 g) granulated sugar
- 3/4 cup (63 g) unsweetened cocoa powder
- 2 teaspoons (8 g) baking powder
- 1 1/2 teaspoons (9 g) baking soda
- 1 teaspoon (2.8 g) kosher salt
- 1 teaspoon (2.3 g) espresso powder
- 1 cup (227 g) buttermilk, whole milk, or coconut milk
- 1/2 cup (99 g) vegetable oil
- 2 large (100 g) eggs
- 2 teaspoons (9.4 g) vanilla extract
- 1 cup (227 g) boiling water
Chocolate Buttercream Frosting (9×13 Recipe)
- 1/2 cup (42 g) unsweetened cocoa powder
- 3/4 cup (169.5 g) butter, softened
- 2 1/2 cups (283.7 g) confectioner’s sugar
- 1/4 cup (56.7 g) milk
- 1 teaspoon (4.7 g) vanilla extract
- 1/4 teaspoon (0.57 g) espresso powder
Instructions
- Preheat oven to 350º F. Prepare one 9×13 baking dish by brushing with homemade chocolate cake pan release (chocolate cake goop), spraying with baking spray or buttering and lightly flouring.
- Whisk together flour, sugar, cocoa, baking powder, baking soda, salt and espresso powder to a large mixing bowl.
- Add milk, vegetable oil, eggs, and vanilla to flour mixture and mix together until well combined. Carefully stir the boiling water into the cake batter and pour into the prepared 9×13 dish.
- Bake for 30-35 minutes, until a toothpick or cake tester inserted in the center comes out clean. You can follow my tips for how to tell when your cake is done.
- Remove from the oven and allow to cool completely.
Chocolate Buttercream Frosting (9×13 Recipe)
- Add cocoa to a large bowl or bowl of stand mixer. Whisk through to remove any lumps.
- Add the butter and cream together butter and cocoa powder until well-combined.
- Add sugar and milk to cocoa mixture by adding 1 cup of sugar followed by about a tablespoon of milk. After each addition has been combined, turn mixer onto a high speed for about a minute. Repeat until all sugar and milk have been added.
- Add vanilla extract and espresso powder and combine well.
- If frosting appears too dry, add more milk, a tablespoon at a time until it reaches the right consistency. If it appears to wet and does not hold its form, add more confectioner’s sugar, a tablespoon at a time until it reaches the right consistency.
- Spread the frosting on top of the cooled cake. Cover and keep on the counter for up to 3 days for best taste.
Notes
1 cup granulated sugar
1/2 cup unsweetened cocoa powder
1 teaspoon baking powder
1/2 teaspoon baking soda
1/2 teaspoon kosher salt
1/2 teaspoon espresso powder
1/2 cup whole milk, buttermilk, or coconut milk
1/4 cup vegetable oil
1 large egg
1/2 teaspoon vanilla extract
1/2 cup boiling water
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Enjoy!
Robyn xo
Hi! Can I use buttermilk for the frosting?
Maddisen, I haven’t used buttermilk to make this frosting,but I have seen that other people have.
Am doing your original recipe 9×13 chocolate cake and can only see directions for the new chocolate cake which is generally fine . However when it comes to the baking time for the 2c version it says to bake for 30-35 minutes and I doubt whether the 1c version would bake the same time. Am going to try for 20 min and go from there. Your input would be appreciated.
Hi Robyn, this recipe says 2 cups of sugar 396 g but the flour says 2 cups 240 g, is there a mistake?
Sata, the grams are correct. The sugar weighs more than the flour so the gram amounts would be different.