Chocolate Sheet Cake
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A luscious chocolate sheet cake topped with silky-smooth, creamy homemade chocolate frosting. It’s moist and so easy to make. It’s the ultimate chocolate cake that’s easy to make for a large group!

I love cake and I love chocolate, so when you give me a chocolate cake I am in heaven! This is the best chocolate sheet cake recipe ever. It is perfectly moist, fluffy, and not too rich. The homemade frosting takes it to the next level too!
Making cake doesn’t have to be difficult. Layered cakes are super pretty, of course, but sometimes they can just be a pain to make. This chocolate sheet cake is great for any occasion, and this strawberry lemon cake is a favorite of mine in the warmer months.
Grab the ingredients you need from your pantry and refrigerator and get to making this moist chocolate sheet cake from scratch!
Why You’ll Love this Chocolate Sheet Cake Recipe
- It will only take you about 15 minutes to prep this entire homemade chocolate sheet cake! And only an hour and 40 minutes to completely finish.
- Sheet cakes are a great way to feed a crowd! This recipe will provide 24 servings.
- This recipe is super easy to follow. It’s a great cake for beginner bakers to make, along with experienced bakers!

Ingredients for Chocolate Sheet Cake
- All purpose flour – Use a high quality all-purpose flour for best results!
- Granulated sugar – You’ll use granulated sugar to sweeten this easy chocolate sheet cake.
- Unsweetened cocoa powder – You can’t have a chocolate cake without chocolate! Use cocoa powder to flavor your sheet cake.
- Baking soda – Baking soda will act as a rising agent for your chocolate sheet cake.
- Baking powder – Having two rising agents helps ensure that you have a super fluffy cake that remains moist.
- Salt – A little pinch of salt helps balance out flavors and brings out the flavor of chocolate really well.
- Buttermilk – If you don’t want to use buttermilk, you can use regular whole milk or 2% if you prefer.
- Large eggs – Allow the eggs to come to room temperature before you add it into the chocolate cake batter.
- Vegetable oil – Feel free to swap out the vegetable oil for olive oil, canola oil, or even melted butter.
- Vanilla extract – A little splash of vanilla creates a wonderful depth of flavor in chocolate sheet cake.
- Boiling water – Boiling water will help to thoroughly incorporate all ingredients in the cake batter.
Ingredients for Chocolate Frosting
- Confectioners’ sugar – Use confectioners sugar to create a sweet and smooth chocolate frosting to top your homemade chocolate sheet cake.
- Unsalted butter – Feel free to use salted butter, just know that the flavor may change a tad if you use salted butter.
- Unsweetened cocoa powder – You’ll use cocoa powder to flavor your chocolate frosting.
- Heavy cream – Heavy cream helps make this frosting perfectly creamy and smooth!
- Vanilla extract – Use a little vanilla extract in the frosting as well as the cake.


How to Make Chocolate Sheet Cake
Line an 18×13 sheet cake pan with parchment paper, leaving the sides of the paper sticking out over the top of the pan. Then, spray lightly with cooking spray and set aside.
Sift together flour, sugar, cocoa powder, baking soda, baking powder and salt in a large bowl. Sifting is important so that it removes any lumps, so sift everything twice if needed. Then set aside the dry ingredients.
In a separate bowl, whisk together buttermilk, room temperature eggs, vegetable oil, and vanilla until thoroughly combined.
Stir the dry ingredients into the wet ingredients until just combined, don’t over-mix!
Pour boiling water into the chocolate cake batter and stir until mixed well. Use a silicone spatula to scrape the sides and bottom of the bowl to ensure everything is mixed well.




Pour the completed cake batter into the previously prepared sheet cake pan and carefully transfer it to the oven.
Bake in the oven for 26-27 minutes until a toothpick can be inserted and comes out clean.
Remove the chocolate sheet cake from the oven and allow it to cool completely in the pan before frosting the cake.
To make the chocolate frosting, beat together the confectioners’ sugar, cocoa powder, heavy cream, and vanilla until light and fluffy. If the frosting is a bit too thick, add some more heavy cream until it thins out a bit!
Smooth the frosting into an even layer across the top of the cake and decorate with anything you want! Then slice and serve!
How to Store Leftover Easy Chocolate Sheet Cake
Store any leftovers of the cake at room temperature for up to 3 days. You can wrap the cake pan in plastic wrap or transfer slices to an air-tight container if you want.
FRIDGE: Store leftover slices of cake in the refrigerator to extend the life of it by a few days.
FREEZER: Freeze an entire chocolate sheet cake or leftover slices in an airtight container, or in a sheet pan wrapped in plastic wrap. Place in the freezer for up to a month. Thaw before eating!
What toppings can I add to this chocolate sheet cake?
Sprinkles are always a must for a fun cake! But you can add chocolate chips, sliced strawberries, candy letters, piped icing for words, and so much more. Get adventurous and add whatever you want to this tasty and simple cake!
Can I make chocolate sheet cake ahead of time?
Absolutely! This cake stores great at room temperature for a few days, so it would be a great option to make ahead of time. If you have a party coming up, make this in advance and it will taste just as wonderful as it would being made the day of.
Pro Tips!
- Make sure you smooth out the cake batter into an even layer so that the cake doesn’t dome in the middle and bakes flat.
- Don’t over-bake your cake, or it will dry out. Once it bounces back in the middle, it’s done!
- If you need to speed things up a bit, feel free to use store-bought chocolate frosting.

Everyone needs a go-to chocolate cake recipe, and this will be yours! I’m sure of it!
More Cake Recipes You’ll Love
- Pineapple Cake is one of my favorite desserts to make for cook-outs! It’s refreshing, fruity, and sweet.
- Do you love Oreos? Then you’re going to fall head over heels for this Oreo Poke Cake.
- Carrot Bundt Cake is such a delicious cake to make around Easter time!
- If you want more bundt cake recipes, then check out this Lemon Bundt Cake recipe.
Did you make this? If you snap a photo, please be sure tag me on Instagram at @julieseatsandtreats or #julieseatsandtreats so I can see your yummy treat!

Chocolate Sheet Cake
Ingredients
Chocolate Sheet Cake
- 2 ½ cups all-purpose flour* (350 grams)
- 2 ½ cups granulated sugar (500 grams)
- ¾ cup unsweetened cocoa powder (75 grams)
- 2 ½ teaspoons baking soda
- 1 teaspoon baking powder
- 1 teaspoon salt
- 1 ¾ cups buttermilk room temperature
- 3 large eggs room temperature
- ½ cup vegetable oil
- 2 teaspoons vanilla extract
- 1 cup boiling water
Chocolate Frosting:
- 5 cups confectioners’ sugar (600 grams)
- 1 ½ cup unsalted butter (340 grams), slightly melted (if cold from fridge, about 45 seconds in the microwave)
- ¾ cup unsweetened cocoa powder (75 grams)
- 4-5 Tablespoons heavy cream 35%
- 2 teaspoons vanilla extract
Instructions
Chocolate Sheet Cake
- Preheat oven to 350 degrees Fahrenheit.
- Line one 18” x 13” sheet cake pan with parchment paper (leave parchment paper slighter higher than the sides of the pan so it’s easier to lift the cake out after). Spray lightly with non-stick cooking spray then set aside.
- In a large bowl, sift together flour, sugar, unsweetened cocoa powder, baking soda, baking powder and salt. Sift together to remove any lumps (you may need to sift this twice). Set the dry ingredients aside for now.
- In a separate large bowl, whisk together buttermilk, eggs, vegetable oil and vanilla until well combined.
- Stir dry ingredients into wet ingredients just until mixed. Do not overmix. Be sure to stir these in by hand – do not use electric beaters for this.
- Pour the boiling water into the cake batter and stir until well mixed. Use a spatula to scrape down sides and bottom of bowl.
- Pour cake mix into the prepared sheet cake pan. This will be very full so be careful when transferring it to the oven.
- Bake in oven for 26 to 27 minutes or until toothpick inserted in middle comes out clean.
- Remove cake from oven and let cool completely in pan before frosting.
Chocolate Frosting
- In a large bowl, beat the confectioners’ sugar, butter, cocoa powder, heavy cream and vanilla until light and fluffy (about 5 minutes). If the frosting seems too thick, beat in an additional tablespoon of heavy cream.
- Smooth an even layer of frosting over the top of the cake and decorate as desired.
- The cake can remain at room temperature (wrapped well in food-safe plastic wrap) for up to 3 days. After 3 days, refrigerate or freeze the leftovers (wrapped tightly in food-safe plastic wrap then placed into a sealed food safe container). Bring the cake back to room temperature before serving.
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