Chocolate Sheet Cake, sometimes called Texas Chocolate Sheet Cake or Texas Skip Cake… a whole lot of names for one cake recipe. It is a rich, moist, chocolatey cake topped with one of the best boiled chocolate frostings you have ever had!
Once the chocolate cake comes out of the oven you pour on the frosting and it forms a delicate crystallized layer over the top. Once you have had this frosting you will never forget it.
Now, if it is a low calorie cake, keto, or “diet” cake that you are looking for- turn back now… this is NOT the recipe for you! But, if you want one of the best chocolate cakes you have ever had, you are in the right place.
Read on-
Boiled Chocolate Frosting
I know that boiled frosting seems counterintuitive, but it works like magic! This is an old fashioned recipe, and our grandmothers knew what they were doing!
By boiling the frosting you allow the sugar to crystalize when it is poured on the cake. You end up with an delicate crystalized layer of frosting on top, and under that layer is warm fudgy frosting!
Buttermilk or Sour Milk
My hand written recipe calls for “sour milk” which is basically the same thing as buttermilk when it comes to baking. Back when this recipe was written you wouldn’t dare buy an entire carton of buttermilk just to use ½ cup.
Instead you mix ½ cup milk with 2 tablespoons of white vinegar and let it sit a few minutes to create a “homemade” buttermilk.
You can use either buttermilk or sour milk, both work great!
How to Make Chocolate Sheet Cake & Boiled Frosting
Start by preheating the oven to 350 degrees. Grease and flour an 18x12x1 sheet pan.
If you are using the sour milk method combine ½ cup milk and 2 tablespoons white vinegar and set aside. You can skip this step if you are using buttermilk.
In a large bowl combine 2 cups flour, 2 cups white sugar, 1 teaspoon salt. Set aside.
In a saucepan over medium heat boil 2 sticks of butter, 1 cup water, and 3 tablespoon cocoa powder. Remove from the heat and stir into the flour/sugar mixture.
Crack and lightly whisk 2 eggs into a seperate bowl. Temper them slightly by adding a little of the warm batter into the eggs. Once they are tempered stir them into the batter.
Add ½ cup buttermilk (or ½ cup sour milk if using that method), 1 teaspoon baking soda, 1 teaspoon vanilla. Stir to combine.
Pour into your prepared sheet pan. Bake for 18-22 minutes until cooked through.
Boiled Chocolate Frosting
While the cake bakes, make the chocolate frosting so it can be poured on as soon as the cake comes out of the oven!
In a saucepan over low heat mix together:
- 1 cup butter
- 3 tablespoon cocoa powder
- 5 tablespoon milk
- 1 teaspoon vanilla
Once that is melted together stir in the powdered sugar. Stir until it is well combined.
Assemble the cake
As soon as the cake comes out of the oven pour on the frosting. Spread it evenly and then let it sit for an hour or two to crystalize and cool.
Serve cut into squares. You can serve with whipped cream, ice cream, or just as is!
Storing Chocolate Cake with Boiled Chocolate Frosting
Cut the cake into squares and store at room temperature, covered, for up to a week. (but I doubt it will last that long!)
Variations on the Chocolate Sheet Cake Recipe
We like this chocolate sheet cake as is, however you can dress this cake up to match your own taste buds. Here are just a few ideas:
- Stir a ½ cup chopped pecans, peanuts, or walnuts into the frosting before pouring over the cake.
- Sift powdered sugar over the frosting after it is poured on the cake for extra flair.
- Add a little mint extract to the frosting and then top each square with an Andes Chocolate Mint.
- Crush 2 Heath Candy Bars and add it to the frosting for a sweet crunch.
Homemade Chocolate Sheet Cake Recipe with Boiled Chocolate Frosting
Homemade Chocolate Sheet Cake with Boiled Chocolate Frosting
Ingredients
Chocolate Sheet Cake
- 2 cups All Purpose Flour
- 2 cups Sugar
- 1 teaspoon Salt
- 1 cup Butter - (salted or unsalted)
- 1 cup Water
- 3 Tablespoons (heaping) Cocoa
- 2 Eggs
- ½ cup buttermilk - If you do not have buttermilk you can use sour milk = mix ½ cup milk with 2 Tablespoons white vinegar and let sit for 2-3 minutes.
- 1 teaspoon Baking Soda
- 1 teaspoon vanilla
Chocolate Frosting
- 1 cup Butter
- 3 Tablespoons Cocoa
- 5 Tablespoons Milk
- 1 teaspoon Vanilla
- 3 ½ cups Powdered Sugar
Instructions
- Preheat the oven to 350. Prepare a large sheet pan (18x12x1) by greasing and flouring.
- If you are using sour milk method- combine ½ cup milk with 2 tablespoon white vinegar and set aside. If you are using buttermilk you can skip this step.
- In a large bowl combine flour, sugar and salt. Set aside.
- In a saucepan over medium high heat bring to a boil 1 cup butter, 1 cup water, and 3 Tablespoons cocoa. Remove from heat and stir into the flour/sugar mixture. Next add 2 slightly beaten eggs (you may want to temper your eggs slightly with a tablespoon of the warm batter ), ½ cup sour milk, 1 teaspoon baking soda, and 1 teaspoon vanilla. Stir to combine. Pour into prepared sheet pan.
- Bake for 18-22 minutes.
- While the cake is baking prepare your frosting so it can be poured on as soon as the cake comes out of the oven.
- In a saucepan over low heat mix together 1 cup butter, 3 tablespoon cocoa powder, 5 tablespoon milk, and 1 teaspoon vanilla. Stir until it is melted and then add the 3 ½ cups powdered sugar. Stir until it is well combined.
- As soon as the cake comes out of the oven pour the frosting over the cake. Smooth with a offset spatula or knife. Let rest 1 hour for the frosting to set before serving.
- Store at room temp, covered, for up to a week.
Recipe Tips and Notes:
Dessert & Cake Recipes
Here are a few other dessert and cake recipes to check out!
- Carrot Cake with Cream Cheese Icing
- Cherry Pie Bars
- Easy Apple Pie Bars
- Summer Berry Cobbler
- Raspberry Lemonade Icebox Cake
Originally posted Sept 17, 2017 Copy & Photos updated on Dec 31, 2019
Deanne Sund says
For years I have been stressing over menus that would use everyday ingredients, normal proportions of ingredients, and of course creative & delicious- not too much to ask, right?!!😬
HALLELUJAH! I Finally found you & your common-sensed, delicious menu ideas! THANK YOU!
Susie says
Oh my gosh… best comment I have ever received! Thank you so much- you totally get it. That is partly why I created this site- nobody has time to chase down lavender syrup or some crazy ingredient like that to only use it one time! Right!? Real food, simple recipes, easy to find ingredients.
John says
This is a “last meal” type of dessert!
Susie says
morbid, but correct. LOL
Alan says
Susie, my mother-in-law used to make this cake, bless her heart
she went home to be with the Lord in 2019 and I’ve been searching for the recipe and came across your site, best cake ever, however, she used granulated sugar instead of confectioners sugar. Would it be possible to substitute for granulated?
Thank you,
Susie Weinrich says
I love it when I can provide a long lost family recipe! It’s the same way with my Iowa ham balls, people comment all the time that their grandparents or in-laws made them but the recipe was lost.
I have not tried it with granulated sugar in the frosting. I tried to look up some similar recipes and they all call for powdered sugar. I think the powdered sugar gives you a smoother frosting.