Name: Devil's Food Sheet Cake (9x13 Recipe)
Prep time: 20 min
Cook time: 35 min
Total time: 55 min
Ingredients: 2 cups (250 g) all-purpose flour; ¾ cup (89 g) Dutch-processed cocoa powder; 2 cups (400 g) granulated sugar; 1 teaspoon baking powder; 2 teaspoons baking soda; ½ teaspoon kosher salt; 1 cup (237 ml) brewed coffee, (hot (regular or decaf)); 1 cup (240 ml) buttermilk, (room temperature); ½ cup (120 ml) vegetable oil; 2 large eggs, (room temperature); 2 teaspoons pure vanilla extract; 6 tablespoons unsalted butter, (softened); 6 tablespoons Dutch-processed cocoa powder; 2 tablespoons honey; 2 teaspoons vanilla extract; 2 cups (250 g) confectioners' sugar; 6 tablespoons whole milk

This Devil’s Food Sheet Cake is rich, moist, and full of deep chocolate flavor, baked in a simple 9×13 pan for easy serving. Hot coffee helps boost the chocolate flavor, while buttermilk keeps the crumb soft and tender. It’s finished with my brownie frosting, making it an easy crowd-pleasing dessert for birthdays, potlucks, or any time you need a simple chocolate cake. If you want a more classic layer cake version, try my Devil’s Food Cake recipe next.

Pan of Devil's Food Sheet Cake on a wooden table from overhead.

Ingredients & Substitutions

Flour: All-purpose flour gives the cake structure, so it holds together, but still stays soft. Cake flour is not recommended because it can make the cake too delicate for this thin batter.
Cocoa Powder: This recipe uses Dutch-processed cocoa for a deep chocolate flavor and dark color. If you only have regular cocoa powder, you can use it, but the cake will taste a little lighter and slightly more bitter.
Sugar: Granulated sugar sweetens the cake and helps keep it moist. Try not to cut it too much because it also balances the strong chocolate and coffee flavors.
Baking Powder & Baking Soda: These help the cake rise and stay fluffy. They work together with the cocoa and buttermilk to create a soft, tender texture.
Coffee: Hot coffee makes the chocolate flavor stronger without making the cake taste like coffee. If needed, you can use hot water instead, but coffee gives the best flavor.
Buttermilk: Buttermilk makes the cake soft and moist. If you don’t have it, mix 1 cup of milk with 1 tablespoon of lemon juice or vinegar and let it sit for 5 minutes.
Oil: Vegetable oil keeps the cake extra moist and soft. Canola oil works too. Butter is not recommended because it can make the cake feel heavier.
Eggs & Vanilla: Eggs help hold everything together, and vanilla adds a warm flavor that makes the chocolate taste even better. Room temperature eggs mix in more easily.
Frosting: After testing a couple of frostings for this cake, I decided on my brownie frosting, which you will want to use on your next batch of brownies, too!

This Devil’s Food Sheet Cake is rich, moist, and deeply chocolatey, baked in a simple 9x13 pan for easy serving. It’s finished with my favorite chocolate frosting that makes every bite extra rich and satisfying!

FAQs

Why use a 9×13 pan for this cake?

A 9×13 pan is the easiest option for this recipe. It bakes evenly, is simple to slice, and makes a perfect sheet cake for serving a crowd without needing layers or extra steps.

Can I make this in a different pan size?

Yes, but the baking time will change. A smaller pan will make a thicker cake that needs more time in the oven. A larger pan will bake faster and result in a thinner cake.

Does the coffee make the cake taste like coffee?

No. The coffee just makes the chocolate flavor stronger. You won’t taste coffee in the finished cake.

Can I use milk instead of buttermilk?

Yes. Mix 1 cup of milk with 1 tablespoon of lemon juice or vinegar. Let it sit for 5 minutes before using.

How do I know when the cake is done?

Insert a toothpick into the center. It should come out with a few moist crumbs, but no wet batter. Start checking around 35 minutes.

Can I make this Devil’s Food Sheet Cake ahead of time?

Yes. Bake it a day ahead, let it cool completely, then cover tightly. Frost right before serving for the best texture.

Can I freeze Devil’s Food Sheet Cake?

Yes. Freeze unfrosted cake (or frosted slices) for up to 2 months. Wrap well and thaw in the fridge before serving.

PIece of Devil's Food Sheet Cake on a metal plate on a wooden table.

What’s the Best Pan for Devil’s Food Sheet Cake?

A 9×13-inch metal baking pan is the best choice for this cake. Metal conducts heat well, which helps the cake bake evenly and gives you a soft, moist crumb with slightly crisp edges.
Light-colored aluminum pans are ideal because they bake more evenly and help prevent overbrowning. Aluminized steel pans also work very well and give similar results.
Glass or ceramic pans can be used, but the cake may take longer to bake in the center, and the edges can brown more quickly. Dark nonstick pans will also work, but they tend to bake the edges faster, which can dry them out slightly.
For best results, fill the pan about halfway so the cake has room to rise evenly.

Close up of a piece of Devil's Food Sheet Cake on a plate.

How to Store Devil’s Food Sheet Cake

Room Temperature: If the cake is unfrosted or lightly frosted, it can be stored covered at room temperature for up to 2 days. Keep it in an airtight container or tightly wrapped so it stays soft and moist.

Refrigerator (best for frosted cake): Because of the chocolate buttercream, frosted cake should be stored in the refrigerator. Cover it well or store in an airtight container for up to 5 days. Let it sit at room temperature for about 20 to 30 minutes before serving so the frosting softens and the cake is tender again.

Freezer: This cake freezes well with or without frosting. Wrap slices or the whole cake tightly in plastic wrap and place in a freezer-safe container for up to 2 months. Thaw overnight in the fridge, then bring to room temperature before serving.