Name: Bumpy Chocolate Cake with Swirled Buttercream and Fudge Icing Recipe
Prep time: 20 min
Cook time: 35 min
Total time: 1 h 5 min
Cuisine: American
Ingredients: 1 3/4 cups all-purpose flour; 1 1/2 teaspoons baking soda; 1/2 teaspoon salt; 3/4 cup unsweetened cocoa powder; 1 3/4 cups granulated sugar; 1 cup unsalted butter, softened; 3 large eggs; 2 teaspoons vanilla extract; 1 cup buttermilk; 1 cup hot water or coffee; 1/2 cup unsalted butter, softened; 1/4 cup vegetable shortening; 3 cups powdered sugar, sifted; 2-3 tablespoons heavy cream or milk; 1 teaspoon vanilla extract; Pinch salt; 3/4 cup heavy cream; 1 1/2 cups granulated sugar; 6 tablespoons unsalted butter; 6 tablespoons unsweetened cocoa powder; Pinch salt; 1 teaspoon vanilla extract

If there’s one dessert I absolutely cannot stop talking about, it’s this unforgettable Bumpy Chocolate Cake with Swirled Buttercream and Fudge Icing Recipe. This cake is a celebration of rich chocolate flavor paired with a unique texture you’ll love—the charming “bumps” created by piped buttercream give every bite a fun, tactile delight. The fudgy icing gracefully cascades over those bumps, creating a luscious blend of silky and fluffy that feels like a little party in your mouth. Once you try this recipe, it’s sure to become a go-to for special occasions or any time you want to impress with a show-stopping chocolate treat.

Ingredients You’ll Need

A clear glass bowl filled with one creamy layer of smooth, light beige frosting with visible swirled texture made by mixing, sitting on a white marbled surface next to a white cloth napkin, photo taken with an iphone --ar 4:5 --v 7

Gathering simple ingredients is the first step to making an extraordinary chocolate cake. Each component plays a crucial role in creating its deep flavor, moist texture, and that irresistible fudgy finish.

All-purpose flour (1 3/4 cups): Provides structure and balance for a tender crumb.
Baking soda (1 1/2 teaspoons): Helps the cake rise beautifully while keeping it light.
Salt (1/2 teaspoon plus a pinch): Enhances the chocolate’s richness and balances sweetness.
Unsweetened cocoa powder (3/4 cup): Delivers intense chocolate flavor and that iconic dark color.
Granulated sugar (1 3/4 cups plus 1 1/2 cups): Sweetens the cake and the fudge icing perfectly.
Unsalted butter (1 cup + 6 tablespoons + 1/2 cup for frosting): Adds moistness and a creamy mouthfeel throughout the cake and frostings.
Large eggs (3): Bind ingredients and provide richness.
Vanilla extract (2 teaspoons + 1 teaspoon in frostings): Boosts sweetness and adds a warm aroma.
Buttermilk (1 cup): Introduces a subtle tang and keeps the cake tender.
Hot water or coffee (1 cup): Intensifies the chocolate depth and thins the batter for a moist texture.
Vegetable shortening (1/4 cup): Keeps the buttercream piping smooth and stable.
Powdered sugar (3 cups, sifted): Sweetens and thickens the buttercream perfectly.
Heavy cream (3 tablespoons for buttercream, 3/4 cup for fudge icing): Adds creaminess and helps achieve that silky melt-in-your-mouth fudge sauce.

TIP

You’ll find the full ingredient list, instructions, and print option in the recipe card below.

How to Make Bumpy Chocolate Cake with Swirled Buttercream and Fudge Icing Recipe

Step 1: Preheat and Prepare

Start by heating your oven to 350 degrees Fahrenheit and greasing a 9×13-inch pan. This ensures your cake cooks evenly and releases easily once baked.

Step 2: Mix Dry Ingredients

Whisk together the all-purpose flour, baking soda, salt, and cocoa powder in a medium bowl. This step evenly distributes your leavening agents and chocolate, setting a solid foundation for your batter.

Step 3: Cream Butter and Sugar

In a separate large bowl, beat softened butter and granulated sugar on medium-high speed until light, fluffy, and pale—about 3 to 4 minutes. This aeration is critical for a tender, airy crumb.

Step 4: Add Eggs and Vanilla

One at a time, beat in the eggs, making sure each is fully incorporated before adding the next. Then stir in the vanilla extract. This layering technique ensures a smooth, uniform batter.

Step 5: Combine Dry and Wet Ingredients

Alternately mix in the dry ingredient mixture and buttermilk, starting and ending with the dry ingredients. Finally, add the hot water or coffee and stir until smooth. The batter will be quite thin, which is perfect for a moist cake.

Step 6: Bake the Cake

Pour the batter into your prepared pan and bake for 30 to 35 minutes. Test with a toothpick—when it comes out clean, your cake is ready. Allow it to cool completely in the pan for about an hour before frosting.

Step 7: Make the Swirled Buttercream

Beat butter and vegetable shortening until silky smooth. Gradually beat in sifted powdered sugar until thick and creamy. Mix in vanilla, a pinch of salt, and heavy cream, just enough to create a thick, pipeable frosting that holds its shape.

Step 8: Pipe the “Bumps”

Transfer the buttercream to a piping bag fitted with a large round tip. Pipe long, even rows of bumps across the cooled cake, spacing each row about one inch apart. Chill the cake for 30 minutes to set the buttercream.

Step 9: Prepare the Fudge Icing

In a saucepan over medium heat, combine heavy cream, granulated sugar, butter, cocoa powder, and a pinch of salt. Stir continuously until it boils gently and thickens slightly, around 4 to 5 minutes. Remove from heat and stir in vanilla extract.

Step 10: Coat the Cake

Let the fudge icing cool slightly until it is still pourable but won’t melt your buttercream. Pour it evenly over the chilled cake, letting it drape naturally over those delightful bumps. Gently tilt the pan to spread without smoothing out the texture. Chill the cake until the icing sets, then slice, serve, and prepare for compliments!

How to Serve Bumpy Chocolate Cake with Swirled Buttercream and Fudge Icing Recipe

A rectangular metal pan contains a single dark brown cake layer as the base. On top of the cake layer, there are five thick, evenly spaced, long lines of creamy light beige frosting running vertically from top to bottom. The frosting lines have a smooth texture with slight swirls and are neatly placed with visible cake edges in between. The pan rests on a white marbled surface photo taken with an iphone --ar 4:5 --v 7

Garnishes

This cake’s visual charm can be elevated with simple garnishes like fresh raspberries for a tart contrast, or a light dusting of cocoa powder or edible gold flakes for a touch of elegance. Crushed nuts or chocolate shavings also add a pleasant crunch.

Side Dishes

Pair your Bumpy Chocolate Cake with whipped cream, fresh berries, or even a scoop of vanilla bean ice cream. A cup of rich coffee or a smooth port wine will also complement the flavors beautifully for a decadent finish.

Creative Ways to Present

Try serving this cake on a rustic wooden board for a cozy vibe or a sleek white platter to highlight the rich colors and luscious texture. You can also cut it into smaller squares for a buffet or party tray, letting guests enjoy the “bumps” in bite-sized form.

Make Ahead and Storage

Storing Leftovers

After your fun celebration, store leftover cake in an airtight container in the refrigerator. The combination of buttercream and fudge icing keeps it moist and delicious for up to 4 days. Let it come to room temperature before serving to enjoy that perfect creamy texture.

Freezing

This cake freezes well if you want to prepare it ahead. Wrap it tightly with plastic wrap and then foil to prevent freezer burn. Freeze for up to 2 months. Thaw overnight in the fridge and chill again briefly before serving.

Reheating

When ready to enjoy, warm individual slices gently in the microwave for about 10-15 seconds to bring out the fudgy richness without melting the buttercream bumps completely. This little trick brings the cake back to life beautifully.

FAQs

Can I use regular milk instead of buttermilk?

Yes, you can substitute regular milk by adding one tablespoon of lemon juice or vinegar per cup of milk to mimic buttermilk’s acidity. This helps achieve the same tender texture and subtle tang in your Bumpy Chocolate Cake with Swirled Buttercream and Fudge Icing Recipe.

What if I don’t have vegetable shortening for the buttercream?

You can replace vegetable shortening with more unsalted butter in the buttercream, though the frosting might be a bit softer. Chilling the cake well after piping will help keep the signature bumps intact.

Can I make this cake gluten-free?

Absolutely! Swap the all-purpose flour for a gluten-free baking blend that includes xanthan gum. Be sure to follow the blend’s substitution ratio to maintain the cake’s texture.

How do I get those perfect bumps every time?

Use a piping bag fitted with a large round tip and pipe with steady pressure, creating long, even rows. Chilling the cake after piping is essential to firm up the bumps before adding the fudge icing, keeping that charming texture crisp.

Can I make the fudge icing ahead of time?

You can prepare the fudge icing a day ahead and store it in the fridge. Before pouring over the cake, gently warm it until pourable but not hot to avoid melting your buttercream pulses. This makes assembly quicker and less stressful.

Final Thoughts

I truly hope you give this Bumpy Chocolate Cake with Swirled Buttercream and Fudge Icing Recipe a try—its rich layers, playful texture, and irresistible fudge topping make it a deliciously satisfying baking adventure. Whether for a birthday, holiday, or simply a joyful weekend treat, this cake is designed to delight everyone lucky enough to have a slice. Happy baking and even happier eating!