Chocolate Sheet Cake

One of the easiest chocolate cakes to make and with an upgraded chocolate buttercream frosting on top! This chocolate sheet cake is SO rich, decadent, and most importantly MOIST. The cake batter comes together in one bowl with a handful of simple ingredients and it's baked into a fluffy, spongy, and perfect single layer sheet. It's topped with buttercream frosting that's made with melted chocolate - which adds a deeper flavor and makes for a less sweet topping.

what makes this chocolate sheet cake so good?

This recipe is adapted from my reader favorite chocolate cake recipe with a few little tweaks to make for a perfect sheet cake. My classic chocolate cake has SO many rave reviews and it's a recipe I (and so many of you!) go back to time and time again - so it was the natural starting point for this cake. Here are just some of the features of this recipe that make it so incredible:

One bowl: The best chocolate cake is not only moist and spongy, it should also be easy to make and require as few dishes as possible. And this cake is all of the above! The batter comes together in one bowl with a handful of ingredients that you probably already have on hand. This cake recipe is so straightforward, easy to follow, and it all requires about 10 minutes of work - but it comes out tasting like something you spent hours making.

Texture: While all of the ingredients work together to give this cake it's incredible texture, three of them stand out for their role. Vinegar, oil, and boiling water each play a huge part in making this cake extra soft, spongy, and moist. Vinegar helps tenderize the cake and contributes to its lift. Meanwhile, oil makes the cake extra moist because it stays liquid even after the cake fully cools (unlike butter which would eventually harden). Finally, the boiling water will help activate the leaveners and helps dissolve larger clumps in the batter, ultimately creating a cake that's fluffy and velvety smooth.

Frosting: Last, but certainly not least, we can't forget the literal icing on the cake! This sheet cake is topped with a chocolate frosting made with a mix of cocoa powder and melted chocolate. If you find regular buttercream to be too sweet, this is the frosting for you! The melted chocolate helps minimize the sweetness and gives the frosting a more interesting flavor that's extra rich, indulgent, and chocolatey.

how to make chocolate sheet cake

I'm not exaggerating when I say this cake batter is one of the easiest to whip up - and it's fail proof. All it involves is whisking together the dry ingredients, whisking in the wet ingredients, and finally, mixing in hot coffee. It's so simple but the results are incredible!

That being said, here are a few key tips to keep in mind to ensure your cake comes out perfect everytime:

1. Choosing the baking pan: For the best cakes, I almost always recommend using a good quality, heavy duty, light colored aluminum pan. Heavy duty metal pans conduct heat perfectly - allowing the cake to bake through at the perfect rate without burning the edges. And just like how it's recommended you wear light colors when it's hot outside, light colored pans are best for baking because darker colored pans will absorb more heat and can burn the outside of the cake!
2. Measuring the flour: Whenever possible, measuring flour using a food scale is always the best way to ensure you have the exact right amount. But if you are using cups, make sure to use a spoon to scoop the flour into your measuring cup. Don't scoop the measuring cup itself into the bag of flour otherwise you can pack in more weight and ultimately dry out the cake!
3. Mixing the batter: As with any cake recipe that uses all-purpose flour, watch out for overmixing! It can overwork the gluten in the flour and shred through the air bubbles in the batter, which will lead to a dense, dry cake. Just mix until the batter is streak free.
4. Baking and cooling: To tell when it's time to pull the cake out, the surface should be evenly puffed and a skewer inserted into the center should come out mostly clean but with a few moist cake crumbs. Once it's baked, make sure to let the cake FULLY cool before you try to frost it - otherwise it will melt the icing.

chocolate buttercream with chocolate

If you're not a huge fan of regular buttercream frosting - wait until you try this one! Adding some melted chocolate to the frosting helps mellow out the sweetness and gives it an all around more complex flavor. It tastes like a mix between classic buttercream and chocolate ganache! It's not too sweet and has a light and creamy texture.

Here's a bit of a closer look into what goes into making this frosting:

1. Choosing the chocolate: Before starting, it's important to choose the right chocolate! The best chocolate to use would be a good quality bar of chocolate - something like Baker's brand or Lindt. Not only is the flavor incredible, but they just melt more smoothly. If there's a brand of chocolate chips that you love to use for melting, go ahead and use it! But otherwise, it's usually best to avoid chocolate chips as some brands specially design them to keep their shape - which is fine when making something like a chocolate chip cookie, but it can make for a gritty and clumpy texture when you try to melt it!
2. Cooling the chocolate: Once the chocolate is melted, the most important step comes: letting the chocolate cool! If the chocolate is too hot, it will melt the frosting. If the frosting cools too much, it will reharden. I find about 15 minutes on my counter is the perfect amount of time for it to cool down, but that can change depending on how cool your home is. What you're essentially looking for is chocolate that's room temperature but still liquid.
3. Powdered sugar and cocoa powder: For the smoothest frosting, sift the powdered sugar and cocoa powder! They can have little clumps that won't properly dissolve into the frosting. Sifting helps ensure everything is nice and smooth!
4. Mixing and adjusting: The frosting should be perfect to use as soon as it's whipped up, but it you find it's a little too thick, you can thin it out with a splash of milk. Start with 1 tablespoon of room temperature milk and add as needed to get the frosting to your desired consistency. If the frosting is too loose, it may mean the chocolate was too hot when it was added in. You can try to fix it by popping it into the fridge for 30-60 minutes then mixing it again once it's chilled slightly.

FAQs

Can you make this into cupcakes or a layered cake?
Make my chocolate cupcakes or classic chocolate cake recipe instead! You can use this same frosting recipe for the cupcakes but you would need to double it for a layer cake.

Can you make this chocolate cake gluten free?
I have a gluten free chocolate cake recipe that you can grab HERE! You can bake that recipe in a 9x13" pan, but you'll probably need to give it a few extra minutes in the oven - so just keep an eye on it.

Can you skip the vinegar?
It helps make the cake extra tender and soft AND helps it rise - so don't skip it!

Can you use olive oil?
You can, but you will be able to taste it. If you like the flavor, then go for it! If you just want an alternative to vegetable oil, you can use any neutral flavored oil (like canola or peanut, for example). A light olive oil would also work and would have a slightly softer flavor than extra virgin.

Can you skip the coffee?
Yes! The coffee won't flavor the cake - it just helps enhance the chocolate flavor. But if you would prefer to leave it out, you absolutely can. Just use plain hot water instead.

chocolate sheet cake storage

This chocolate sheet cake will keep for about 5-7 days at room temperature. Thanks to the sugar in the frosting, it helps naturally preserve the cake even without refrigeration. The cake will keep moist until the VERY last day!

Keep it covered with plastic wrap and avoid slicing until right before you plan on serving - the less air the cake is exposed to, the longer it'll stay moist. If it's a particularly warmer season, then I would store the cake in the fridge so the frosting doesn't soften too much.

check out these other chocolate recipes!

• Chocolate Mousse Cake
• Chocolate Espresso Cake
• No Bake Chocolate Cheesecake
• BEST Gooey Brownies
• Chocolate Peanut Butter Fudge Bars
• White Chocolate Biscoff Truffles

Lastly, if you made this or any of my recipes, be sure to leave a comment and review below! I love hearing your thoughts! Also tag me on Instagram @eatsdelightfulblog so I can see what you're making.

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Enjoy!

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