Homemade Chocolate Brownie Cake Recipe
This homemade Chocolate Brownie Cake recipe creates a delicious hybrid of chocolate brownies and a Texas sheet cake. The cake is topped with luscious chocolate icing made from scratch.

Most brownie recipes only make an 8×8 or 9×9 batch. I came up with this Homemade Chocolate Brownie Cake in order to make a larger batch.
I combined some elements of a few recipes, tweaked them a little, and bam! These chocolate brownies are what some may call a Brownie Sheet Cake.

Ingredients
To make a 9×13 pan of chocolate brownie cake from scratch, you need the following ingredients:
Chocolate Syrup
- ¼ cup unsweetened cocoa powder
- ½ cup water
- 1 cup sugar
- 1 teaspoon vanilla
- ¼ teaspoon salt
Brownie Cake Batter
- 1½ cups all-purpose flour
- 1 teaspoon baking powder
- 1 teaspoon salt
- 2 tablespoons espresso powder
- 10 tablespoons butter (= 1 stick + 2 tablespoons)
- ¾ cup baking cocoa
- ¼ cup vegetable oil
- 2 cups sugar
- 4 large eggs
- 2 teaspoons vanilla extract
- ⅔ cup chocolate chips
- Chocolate Syrup
Chocolate Icing
- 1¼ cups chocolate chips
- 3 tablespoons corn syrup
- 1 stick butter
How To Make a Chocolate Brownie Cake
Start by making a simple chocolate syrup. Just sugar, cocoa, water, vanilla, and a little salt.

The reason to make the syrup first is that it has to come to a boil and then cool. It will thicken some during the cooling period.
While the syrup is cooling, start the other aspects of the brownies, like preparing a 9×13 pan. I like to line it with aluminum foil sprayed with non-stick spray.

Next, gather the other ingredients together. (Above is flour, baking powder, salt, and espresso powder.)

It’s best to add eggs one at a time. I like to crack all of mine into a little glass bowl before adding them. You never know when you will run across a bad egg.
Now, microwave the butter until melted in a medium-size glass bowl. Add cocoa and oil and whisk until smooth.
Transfer the cocoa mixture to a bowl of an electric mixer. Stir in the sugar and add eggs, one at a time, mixing well after each addition. Add vanilla.
Gradually add the flour mixture. Pour in chocolate syrup and chocolate chips.

Baking Time
Pour batter into prepared 13×9 pan and bake for 25-30 minutes or until done. Let cool before icing.

This is how it looks before the icing is added.

The icing is a simple chocolate glaze made with chocolate chips, butter, and a little corn syrup.
To make the icing, melt chocolate chips and butter together in a microwave-safe bowl in 30-second intervals on high, stirring well after each segment. (It took me a total of one minute + an additional 10 seconds.)
Add corn syrup and stir until smooth. Let sit for 5 minutes before pouring over brownies.

Chocolate Brownie Cake
Ingredients
Method
- To make the syrup: in a medium or large saucepan, whisk the cocoa powder and sugar until well blended. Add water and whisk over medium-high until it starts to boil and becomes a little frothy. Continue boiling for approximately 3 minutes. Reduce heat and allow to simmer for 2 more minutes. Remove from the heat and add salt. Let cool.
- Preheat oven to 350 degrees. Line bottom of 13×9 pan with aluminum foil and spray with non-stick cooking spray.
- Combine flour, baking powder, salt, and espresso powder and set aside.
- Microwave butter until melted in a medium size glass bowl. Add cocoa and oil and whisk until smooth.
- Transfer cocoa mixture to a bowl of an electric mixer. Stir in sugar. Add eggs, one at a time, mixing well after each addition. Add vanilla. Gradually add flour mixture. Pour in chocolate syrup and chocolate chips.
- Pour batter into prepared 13×9 pan and bake for 25-30 minutes or until done. Let cool before icing.
- To make the icing: Melt chocolate chips and butter together in a microwave-safe bowl in 30 second intervals on high, stirring well after each segment. (It took me a total of one minute + an additional 10 seconds.) Add corn syrup and stir until smooth. Let sit for 5 minutes before pouring over brownies.
Nutrition
Video
Tried this recipe?
Let us know how it was!
Like chocolate? Be sure to check out these other delicious chocolatey desserts:
- Nutella Bread (aka Chocolate Bread) – Luscious Nutella enrobed in a homemade sweet dough – it’s great for breakfast, snack, and dessert!
- Brown Sugar Blondies – This is the recipe for those who really want a brownie but can’t have chocolate.

OOoo how yummy! I bet my hubby would love this!
that looks SO rich!!
I should not of seen this before dinner. My tummy is grumbling! I love chocolate. 🙂
Anything with a stick of butter in it has to be good. Looks amazing!
Oh, these look so good! Can’t wait to try them!
Hello LOVER!!! This looks amazing!
Homemade brownies are delicious, I will have to try your recipe
OMG! This looks utterly amazing! My son makes something similar but I think he needs to add the syrup. I’m going to show him this.
Happy SITS Saturday Sharefest!
You had me at brownie but then you took it over the top! I might do this for my little guys 2nd birthday! Great idea. Thanks for sharing.
wowza! Really looking good there!
You just had to go there today. I was all good until I saw that brownie. Man that chocolate icing looks so good.
oh man! the chocolate looks so so so so good on the brownie!
That looks fantastic!
looks delicious….I love the way you tweak, mix and match your recipes!
Oh goodness..this looks heavenly!
This would be good without the icing. I love the crust on the brownies!