Skip to Content

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.

Sliced chocolate brownie cake and a metal spatula.

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.

Mound of cocoa powder and sugar on a white background.

How To Make a Chocolate Brownie Cake

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 tsp vanilla
  • ¼ tsp salt

Brownie Cake Batter

  • 1½ cups all-purpose flour
  • 1 tsp baking powder
  • 1 tsp salt
  • 2 Tbsp espresso powder
  • 10 Tbsp butter
  • ¾ cup baking cocoa
  • ¼ cup vegetable oil
  • 2 cups sugar
  • 4 large eggs
  • 2 tsp vanilla extract
  • two-thirds cup chocolate chips
  • Chocolate Syrup

Chocolate Icing

  • 1¼ cups chocolate chips
  • 3 Tbsp corn syrup
  • 1 stick butter

Start off by making a simple chocolate syrup. Just sugar, cocoa, water, vanilla, and a little salt.

Boiling chocolate in a small saucepan.

The reason to make the syrup first is because 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 that has been sprayed with non-stick spray.

All-purpose flour and espresso in a glass bowl.

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

Eggs in a small glass bowl.

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 it is 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.

Brownie batter on a whisk attachment in a mixing bowl.

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

Baked brownie cake without icing.

This is how it looks before the icing is added.

Chocolate chips in a glass bowl with a stick of butter.

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.

Sliced chocolate brownie cake and a metal spatula.

Chocolate Brownie Cake

Lynda
Chocolate Brownie Cake – this dessert recipe is so good. It's a mix between a brownie and chocolate sheet cake. Yum!
4.59 from 51 votes
Prep Time 15 mins
Cook Time 40 mins
Total Time 55 mins
Course Desserts
Cuisine American
Servings 16 slices
Calories 492 kcal

Ingredients
  

Chocolate Syrup

  • ¼ cup unsweetened cocoa powder
  • ½ cup water
  • 1 cup sugar
  • 1 tsp vanilla
  • ¼ tsp salt

Brownie Batter

  • cups all-purpose flour
  • 1 tsp baking powder
  • 1 tsp salt
  • 2 Tbsp espresso powder
  • 10 Tbsp butter
  • ¾ cup baking cocoa
  • ¼ cup vegetable oil
  • 2 cups sugar
  • 4 large eggs
  • 2 tsp vanilla extract
  • two-thirds cup chocolate chips
  • Chocolate Syrup

Chocolate Icing

  • cups chocolate chips
  • 3 Tbsp corn syrup
  • 1 stick butter

Instructions
 

  • 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

Serving: 1sliceCalories: 492kcalCarbohydrates: 68gProtein: 5gFat: 24gSaturated Fat: 13gPolyunsaturated Fat: 10gTrans Fat: 1gCholesterol: 81mgSodium: 340mgFiber: 3gSugar: 53g
Keyword brownie, cake, chocolate
Tried this recipe?Mention @SouthernKissed or tag #SouthernKissed!
Iced brownie cake in a foil lined baking pan.

Like chocolate? Be sure to check out these other delicious chocolatey desserts:

Sharing is caring!

Honor Allen
Previous
Honor Allen - US Oyster Shucking Champ
Orange roll
Next
All Steak's Orange Rolls (Recipe Clone)
Recipe Rating