Every now and then, I get an urge for old-school recipes. Like this old-school Chocolate Sheet Cake, with its moist brownie-like texture and sweet, crackly chocolate frosting.
I love its down-home charm - the way it's dressy by having a frosting, but unfussy because it's just a short little brownie. You can feed lots of people since it's baked in a large pan, making it perfect for potlucks and casual parties - just like Earthquake Cake from Scratch, another old-fashioned dessert.
This cake is adapted, ever so slightly, from a recipe I remembered from my mom's recipe box. (Remember recipe boxes?!) I love that it, like all great home-cooking recipes, takes simple ingredients that I already have in my kitchen. And, it also doesn't take long to make.
Jump to:
Ingredients
My mom's recipe card calls it "Vicki's Chocolate Sheet Cake and Icing." I've tweaked it ever so slightly.
I love that recipe card recipes can't be too long or complicated. Index cards don't have much room!
As you can see, the chocolate cake takes just some simple household staples.
I use all-purpose flour. I expect that a one-for-one gluten-free flour blend would work okay.
As always, use unsweetened cocoa powder. It's shelf-stable and will last a long time. I've used Hershey's cocoa powder and Saco cocoa powder in the past. Trader Joe's brand and the BJ's club store brand are also cost-effective and work well.
Instead of melting butter, we use vegetable oil in this cake. I like this! I accidentally cut the quantity of oil in half the first time I made it - and it is perfect this way.
Water also adds moisture; don't skip it. Vanilla extract rounds out the flavor.
Eggs provide structure as well as leavening. Since this cake has no baking powder or soda, you must use eggs to create a lighter texture.
Not pictured here is chopped nuts. I personally prefer the cake without nuts. But walnuts or pecans would both be delicious in this recipe.
My daughter is super-excited whenever I make this "brownie cake," because she loves the icing. It's an easy, candy-like icing made with just a few ingredients.
I use granulated sugar here again. Brown sugar should work in a pinch. I don't think powdered sugar would, though, since it has cornstarch.
Unsalted butter and milk contribute to the candy-like texture of the icing. Use salted butter if that's what you have, but I recommend cutting the salt in the cake by half if you do. I use 1% or 2% dairy milk.
I use semisweet or dark chocolate chips. I don't recommend milk chocolate chips, as I find they don't melt well. As always, vanilla extract enhances the flavor.
How to Make a Chocolate Sheet Cake
One: Mix together all dry ingredients in a bowl.
Two: Using a wire whisk, mix in the wet ingredients. Whisk well to combine. Then, stir in the nuts if you're using them.
Three: Pour batter into a greased 15-inch jelly roll pan.
Four: Bake for 25 minutes, until a toothpick inserted into the middle comes out with just a few small crumbs on it. I reduced the oil in this recipe, so be sure not to overbake!
Let your cake cool completely before frosting. I usually wait 45 minutes from when I remove the cake from the oven until I start the icing.
Five: To make the icing, combine the sugar, butter, and milk in a saucepan. Cook over medium-low heat, stirring often, to melt the butter and the sugar.
Six: Stirring constantly, bring the mixture to a gentle boil. That means you have bubbles in the middle of the pot, and not just the edges. Stop stirring, and boil for 30 seconds. (Yes, I set a timer for this.)
Seven: Add the chocolate chips and vanilla. Stir until the chocolate chips are melted and everything has slightly thickened. (I usually do this over low heat as well.)
Eight: Pour and spread the warm icing over the cooled cake.
The warm icing sinks into the cake a little bit, in the best way.
Let the icing cool and set completely before cutting and serving.
Storage
Store the cake, covered, at room temperature. Since I cut the oil in the recipe, it will dry out a little if not covered.
We often cover our jelly roll pan with foil to seal it. We cut pieces of cake as we want them, and the cake stays good this way for at least 4-5 days. If it's going to take you longer than that to finish it, I recommend putting the remaining cake in a sealed storage container.
Top Tip
I've said it many times, but since it's so thin, be sure not to overbake this cake!
Chocolate Sheet Cake FAQs
A regular cake is baked in a 9x13 inch pan (interestingly, also sometimes called a sheet cake pan), or baked in round pans to make a layer cake. A sheet cake like this recipe is made in a larger pan, either a 15-inch jelly roll pan or an 18-inch rimmed baking sheet.
Chocolate sheet cake is a basic chocolate cake recipe, with a simple sugary icing. Texas brownies usually take coffee and buttermilk or sour cream, and have a much bigger quantity of icing.
Technically, no, but if you pour warm icing on a warm cake, much of the icing will slide off the sides. This will mean more icing on the edges (delicious!), but less icing on the cake (ðŸ˜). You'll have best results if you let your cake cool.
Other Homey Recipes
Looking for other homestyle favorites? Here's more of my favorites from my mom's recipe box:
I hope this becomes a recipe you'll return to. If you try it, a star rating below helps others find it - and I'd love to hear how yours turns out in the comments! 💕 Questions or trouble? Drop a note, and I'll do my best to help.
📖 Recipe
Chocolate Sheet Cake
Ingredients
Cake
- 1 ½ cups flour (180 grams)
- 2 cups sugar (396 grams)
- ½ cup cocoa powder (40 grams)
- 1 teaspoon table salt
- ½ cup vegetable oil (112 grams)
- ¼ cup water (60 grams)
- 4 eggs
- 2 teaspoons vanilla
- ½ cup nuts (60 grams, chopped walnuts or pecans) (optional)
Icing
- 1 cup sugar (198 grams)
- 6 tablespoons butter (84 grams)
- 6 tablespoons milk (90 grams)
- ½ cup chocolate chips (85 grams)
- 1 teaspoon vanilla
Instructions
Cake
- Mix dry ingredients in a large mixing bowl.
- Add wet ingredients and whisk well to combine. Use a rubber spatula to stir in nuts, if desired.
- Spread batter in a greased jelly roll (15-inch) pan. Bake at 325F for 25 minutes, until a toothpick inserted in the center comes with just a few small crumbs.
- Cool completely before icing. I usually let it cool 45 minutes before I start the icing.
Icing
- Combine sugar, butter, and milk in a saucepan. Heat over medium-low heat, stirring often, to dissolve the sugar and melt the butter. Don't rush this.
- Once everything is dissolved, bring the mixture to a gentle boil, stirring constantly.
- Stop stirring, and let the mixture boil for 30 seconds. (I set a timer so I don't over- or under-cook it.)
- Add chocolate chips and vanilla. Keep over low heat and stir until chocolate chips are melted and the icing thickens.
- Pour onto the cooled cake and let set before serving.
- Cut into pieces as you serve, to prevent edges from drying out as much. Store, covered, at room temperature for 4-5 days.
Notes
Nutrition
(Originally written in 2016. Updated in October 2018, and rewritten again with new text, updated instructions, and updated photos in February 2025.)
Leona Konkel says
I mean, it's my recipe so clearly I love it. But the best thing is when my daughter is so excited when I'm making it!