Chocolate Sheet Cake with Rich Cocoa Frosting Recipe

Introduction

This classic Chocolate Sheet Cake is moist, rich, and incredibly easy to make. Perfect for gatherings or a simple dessert craving, it features a smooth cocoa frosting and optional walnuts for added texture. You’ll love how quickly it comes together and disappears!

Ingredients

• 1 cup water
• 1 cup unsalted butter (divided: 1 cup + ½ cup)
• 2 cups all-purpose flour
• 2 cups granulated sugar
• ½ cup unsweetened cocoa powder (divided: ½ cup + ¼ cup)
• 1 ½ teaspoons baking soda
• ½ teaspoon salt
• 2 large eggs
• 1 teaspoon vanilla extract (divided: 1 tsp + 1 tsp)
• ½ cup sour milk
• ⅓ cup sour milk
• 2 ⅔ cups powdered sugar
• 1 cup walnuts (optional)

Instructions

1. Step 1: Preheat the oven to 350º F. Grease and flour a 15×11 inch jelly roll pan.
2. Step 2: In a small saucepan, bring 1 cup water and 1 cup butter to a boil.
3. Step 3: In a large bowl, mix together flour, granulated sugar, ½ cup cocoa powder, baking soda, and salt. Set aside.
4. Step 4: In a separate container, whisk together ½ cup sour milk, eggs, and 1 teaspoon vanilla extract until combined.
5. Step 5: Pour the boiling water and butter mixture into the flour mixture and stir until combined.
6. Step 6: Add the milk and egg mixture to the batter and mix until smooth.
7. Step 7: Pour the batter into the prepared pan and bake 20-25 minutes, or until a toothpick inserted in the center comes out clean.
8. Step 8: While the cake bakes, prepare the frosting. In a saucepan over medium heat, heat ½ cup butter, ⅓ cup sour milk, and ¼ cup cocoa powder. Bring to a boil, stirring frequently.
9. Step 9: Remove the frosting mixture from heat and stir in 1 teaspoon vanilla extract and powdered sugar until smooth and pourable.
10. Step 10: If desired, gently fold in walnuts or sprinkle them on top after frosting.
11. Step 11: Immediately pour the warm frosting over the warm cake and spread evenly into a thin layer.
12. Step 12: Let the frosting set for about an hour before serving.

Tips & Variations

• Use buttermilk instead of sour milk for a slightly tangier flavor.
• Add a pinch of instant espresso powder to intensify the chocolate flavor.
• For a nut-free version, omit walnuts or substitute with chocolate chips.
• Make sure to pour the frosting while the cake is still warm to ensure it spreads smoothly and absorbs well.

Storage

Store the cake covered at room temperature for up to 3 days, or refrigerate for up to a week. If refrigerated, bring to room temperature before serving for best texture. Leftover cake can be gently reheated in the microwave for a few seconds.

How to Serve

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this cake gluten-free?

Yes, you can substitute the all-purpose flour with a gluten-free baking blend. Be sure the blend contains xanthan gum or another binder for best results.

What is sour milk, and how do I make it?

Sour milk is regular milk soured with acid to mimic buttermilk. To make, add 1 tablespoon of lemon juice or white vinegar to ½ cup milk, stir, and let it sit for 5-10 minutes before using.

Chocolate Sheet Cake with Rich Cocoa Frosting Recipe

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This classic Chocolate Sheet Cake recipe delivers a rich, moist, and tender cake topped with a luscious, glossy chocolate frosting. Perfect for gatherings or a simple family dessert, it bakes quickly in a jelly roll pan for easy serving and combines the deep flavor of cocoa with a perfectly balanced sweetness.

• Author: Elena
• Prep Time: 15 minutes
• Cook Time: 25 minutes
• Total Time: 40 minutes
• Yield: 12 servings 1x
• Category: Baking
• Method: Baking
• Cuisine: American

Ingredients

Scale 1x2x3x

Cake

• 1 cup water
• 1 cup unsalted butter
• 2 cups all-purpose flour
• 2 cups granulated sugar
• 1/2 cup unsweetened cocoa powder
• 1 1/2 teaspoons baking soda
• 1/2 teaspoon salt
• 2 large eggs
• 1 teaspoon vanilla extract
• 1/2 cup sour milk (see notes below)

Frosting

• 1/2 cup unsalted butter
• 1/3 cup sour milk (see notes below)
• 1/4 cup unsweetened cocoa powder
• 2 2/3 cups powdered sugar
• 1 teaspoon vanilla extract
• 1 cup walnuts (optional)

Instructions

1. Preheat Oven and Prepare Pan: Preheat your oven to 350º F. Grease and flour a 15 by 11 inch jelly roll pan to ensure the cake doesn’t stick.
2. Boil Water and Butter: In a small saucepan, bring together 1 cup water and 1 cup unsalted butter to a boil, which will melt the butter and help dissolve cocoa for a smooth batter.
3. Mix Dry Ingredients: In a large bowl, combine 2 cups all-purpose flour, 2 cups granulated sugar, 1/2 cup unsweetened cocoa powder, 1 1/2 teaspoons baking soda, and 1/2 teaspoon salt, mixing thoroughly and setting aside.
4. Whisk Wet Ingredients: In a separate container, whisk together 1/2 cup sour milk, 2 large eggs, and 1 teaspoon vanilla extract until well blended.
5. Combine Mixtures: Pour the boiling butter and water mixture into the dry ingredients and stir until combined. Then, add the wet egg and milk mixture and mix until the batter is smooth and homogenous.
6. Bake the Cake: Pour the batter into the prepared pan and bake for 20 to 25 minutes, or until a toothpick inserted into the center comes out clean, indicating the cake is done.
7. Prepare Frosting While Warm: As soon as you remove the cake from the oven, start the frosting. This ensures it stays warm and spreadable to absorb into the cake.
8. Make the Frosting: Heat 1/2 cup unsalted butter, 1/3 cup sour milk, and 1/4 cup unsweetened cocoa powder in a saucepan over medium heat, stirring frequently until the mixture comes to a boil.
9. Finish Frosting: Remove from heat and stir in 1 teaspoon vanilla extract and 2 2/3 cups powdered sugar until you achieve a smooth, pourable consistency suitable for spreading.
10. Add Nuts (Optional): If using, fold 1 cup chopped walnuts into the frosting gently or sprinkle them on top after frosting the cake.
11. Frost the Cake: Pour the warm frosting evenly over the warm cake and spread into a thin, even layer.
12. Set and Serve: Allow the frosting to set for about one hour before slicing and serving to enjoy optimal texture and flavor.

Notes

• Sour milk can be made by adding 1/2 tablespoon of lemon juice or white vinegar to 1/2 cup of milk and letting it sit for 5-10 minutes until curdled.
• Use a 15×11 inch jelly roll pan for even baking and appropriate thickness.
• Walnuts are optional but add a nice crunch and flavor to the frosting.
• Ensure to frost the cake immediately after baking while the cake and frosting are warm for better absorption and flavor.

Keywords: Chocolate sheet cake, easy chocolate cake, frosted chocolate cake, classic chocolate dessert, chocolate cake recipe