Single Layer Chocolate Cake with Rich Cocoa Frosting

Sometimes you just need a slice of deep, dark chocolate cake without the stress of stacking multiple layers or crumb-coating a tower. This Single Layer Chocolate Cake with Rich Cocoa Frosting is the ultimate solution for your sweet cravings. It features a tender, moist crumb and a velvety frosting that comes together in minutes. Whether you are celebrating a small win or just treating yourself on a Tuesday night, this cake delivers bakery-quality results with half the effort of a traditional layer cake.

Recipe Information

• Prep Time: 15 minutes
• Cook Time: 30 minutes
• Total Time: 45 minutes
• Servings: 8 servings
• Difficulty: Easy

Nutrition values

• Calories: 345 kcal
• Protein: 4g
• Carbs: 49g

Why Make This Single Layer Chocolate Cake with Rich Cocoa Frosting

This recipe is a game-changer for home bakers. First, it uses simple pantry staples that you likely already have in your kitchen. Second, the single-layer format means you don’t have to worry about cakes sliding or uneven tiers. It is the perfect “snacking cake” that stays moist for days thanks to the addition of boiling water in the batter. Finally, the rich cocoa frosting is thick, fudgy, and spreads like a dream, providing the perfect contrast to the light cake base.

Ingredients

For the Cake:

• 1 cup all-purpose flour
• 1 cup granulated sugar
• 1/3 cup unsweetened cocoa powder
• 1 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1/2 teaspoon salt
• 1 large egg (room temperature)
• 1/2 cup whole milk
• 1/4 cup vegetable oil
• 1 teaspoon vanilla extract
• 1/2 cup boiling water

For the Rich Cocoa Frosting:

• 1/4 cup unsalted butter, melted
• 1/3 cup unsweetened cocoa powder
• 1 1/2 cups powdered sugar
• 3 tablespoons milk
• 1/2 teaspoon vanilla extract

Directions

Step 1: Preparation

Preheat your oven to 350°F (175°C). Grease a 9-inch round cake pan with butter or non-stick spray. For easy removal, line the bottom with a circle of parchment paper. This ensures your cake pops out perfectly without sticking.

Step 2: Mix the Dry Ingredients

In a large mixing bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt. Make sure there are no large lumps of cocoa powder remaining. Sifting the cocoa powder beforehand can help achieve a smoother batter.

Step 3: Add Wet Ingredients

Add the egg, milk, oil, and vanilla extract to the dry ingredients. Use a hand mixer or a whisk to beat the mixture on medium speed for about two minutes. The batter will look thick at this stage, which is completely normal.

Step 4: Incorporate Boiling Water

Stir in the boiling water by hand. The batter will become very thin and watery, but don’t panic! This is the secret to a moist cake with a fine crumb. The hot water “blooms” the cocoa powder, intensifying the chocolate flavor.

Step 5: Bake the Cake

Pour the batter into the prepared pan. Bake for 30 to 35 minutes. Test the center with a toothpick; it should come out clean or with just a few moist crumbs. Let the cake cool completely in the pan on a wire rack before frosting.

Step 6: Prepare the Cocoa Frosting

While the cake cools, whisk the melted butter and cocoa powder together in a medium bowl. Gradually add the powdered sugar and milk, whisking until smooth. Stir in the vanilla. If the frosting is too thick, add a teaspoon of milk. If it is too thin, add a little more powdered sugar.

Step 7: Frost and Serve

Once the cake is cold to the touch, spread the frosting evenly over the top. You can use an offset spatula to create decorative swirls. Slice into eight wedges and enjoy immediately.

Expert Tips for Perfect Single Layer Chocolate Cake with Rich Cocoa Frosting

• Use Room Temperature Ingredients: Ensure your egg and milk are at room temperature so they emulsify properly into the batter.
• Don’t Overbake: Check the cake at the 28-minute mark. Overbaking leads to a dry cake, and we want this to be fudgy and soft.
• Bloom the Cocoa: Never skip the boiling water. It dissolves the cocoa particles and releases a deeper chocolate aroma and taste.
• Cool Completely: If you frost a warm cake, the frosting will melt and slide off. Patience is key!

Delicious Variations

• Mocha Twist: Substitute the boiling water with hot brewed coffee to enhance the chocolate notes.
• Peanut Butter Swirl: Swirl 1/4 cup of creamy peanut butter into the batter before baking for a salty-sweet combo.
• Salted Caramel: Drizzle salted caramel sauce over the frosting for an extra decadent finish.
• Gluten-Free: Swap the all-purpose flour for a high-quality 1:1 gluten-free flour blend.

Frequently Asked Questions

Can I use Dutch-processed cocoa powder?
Yes! Dutch-processed cocoa will give you an even darker color and a smoother, less acidic chocolate flavor. It works beautifully in this recipe.

How should I store this cake?
Keep the cake in an airtight container at room temperature for up to 3 days. For longer storage, refrigerate for up to 5 days, but let it come to room temperature before serving for the best texture.

Can I make this in a square pan?
Absolutely. An 8×8 inch square baking pan works perfectly. The baking time may vary slightly, so start checking for doneness around 25 minutes.

Why is my frosting grainy?
Grainy frosting usually happens if the powdered sugar isn’t sifted or if the butter wasn’t fully incorporated. Whisk vigorously or use a hand mixer to achieve a silky finish.

Can I freeze this cake?
Yes, you can freeze the unfrosted cake. Wrap it tightly in plastic wrap and aluminum foil for up to 3 months. Thaw at room temperature before frosting.

Conclusion

This Single Layer Chocolate Cake with Rich Cocoa Frosting proves that you don’t need a special occasion to enjoy a spectacular dessert. Its simplicity is its strength, offering a reliable, delicious result every single time. With its moist texture and intensely chocolatey frosting, it is bound to become a staple in your recipe collection. Happy baking!

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