Bumpy Cake

Bumpy Cake is a delightful dessert that features fluffy layers of moist chocolate cake topped with luscious buttercream frostings and a decadent fudge glaze. Originating from the Midwestern United States, this cake is both a tribute to nostalgia and a centerpiece for celebrations. Each bite offers a chewy texture mixed with smooth icing—creating an irresistible combination that keeps you coming back for more. What keeps this cake memorable is its unique ridged appearance, which not only looks impressive but also gives it a whimsical touch that both kids and adults adore.

The first time I encountered Bumpy Cake was at a friend’s birthday party, and I was instantly captivated by its distinct look and rich flavor. The presentation on the platter was enough to spark my interest, but the taste? Pure magic! Baking this cake at home brings back that same joy and excitement. Both easy to make and a crowd-pleaser, it’s perfect for birthday celebrations, potlucks, or simply an indulgent treat at home. There’s something truly special about baking this cake and sharing slices with loved ones. I can’t wait for you to try it!

How to Make Bumpy Cake

1. Prep the pan: Preheat your oven to 350°F (177ºC). Spray a 9×13-inch cake pan with nonstick spray to avoid any sticking.
2. Bloom the cocoa: In the bowl of a stand mixer, whisk together 1/2 cup unsweetened cocoa powder, 1 1/2 teaspoons baking soda, and 1/2 teaspoon table salt. Pour in 1/2 cup hot brewed coffee and mix on low speed for about 15–20 seconds until the mixture is smooth.
3. Add the wet ingredients: Add 1/2 cup vegetable oil and 1 cup buttermilk to the bowl and mix until fully combined. Then, add 2 teaspoons vanilla extract and 2 room-temperature eggs, beating on medium speed for 1–2 minutes until smooth.
4. Finish the batter: Gradually add in 1 3/4 cups granulated sugar and 2 cups all-purpose flour, mixing on medium speed just until there are no flour streaks left. Don’t worry if the batter seems thinner than typical cake batter—but that’s perfectly normal!
5. Bake the cake: Pour the batter into your prepared pan and bake for 30–35 minutes, or until the center springs back lightly when touched and loses its glossy appearance. A toothpick inserted into the center should come out with a few moist crumbs.
6. Cool and chill: Allow the cake to cool in the pan for about 20–30 minutes. After that, take it out and chill it in the freezer for 20 minutes to firm up.
7. Make the buttercream: While the cake chills, beat 6 tablespoons of softened unsalted butter on high speed until it’s creamy. Next, add 1/8 teaspoon salt, 2 cups powdered sugar, and 1 teaspoon vanilla extract, plus 1 tablespoon buttermilk. Start mixing on low, then increase to medium-high, beating until thick and fluffy—add an extra tablespoon of buttermilk if necessary to reach a smooth consistency.
8. Pipe the bumps: Transfer the buttercream to a piping bag fitted with a large round tip. Pipe thick horizontal ridges across the short side of the cake, leaving about 1/2 to 1 inch in between each row.
9. Freeze the ridges: Place the cake back in the freezer for about 40 minutes, or until the buttercream ridges feel very firm to the touch.
10. Make the fudge frosting: In a medium saucepan, combine 1/2 cup buttermilk, 2 tablespoons corn syrup, 1/2 cup unsweetened cocoa powder, and 1/2 cup unsalted butter with 1/4 teaspoon salt. Cook over medium-low heat, stirring constantly, until the butter melts and the mixture begins to bubble.
11. Finish the frosting: Remove from heat and whisk in 4 cups powdered sugar and 1 teaspoon vanilla until smooth and glossy. Let the frosting cool slightly while the cake finishes chilling.
12. Frost the cake: Take the chilled cake out of the freezer and spoon the warm fudge frosting over the buttercream ridges and the cake, covering everything completely. Gently tilt the pan to help the frosting spread evenly without needing a spatula.
13. Chill and serve: Refrigerate the cake until the frosting is fully set. To enjoy the best texture, let slices sit out at room temperature for about 15–20 minutes before serving.

Storing & Reheating

To store your Bumpy Cake, keep it covered at room temperature for up to 2 days for optimal texture. If you need to store it longer, refrigerate it, keeping it in an airtight container for up to a week. For longer storage, you can freeze it for up to 3 months. Wrap it tightly in plastic wrap or foil and place it in a freezer-safe container. When you’re ready to enjoy it again, simply thaw it in the fridge overnight. Reheat individual slices in the microwave for around 10-15 seconds to bring them back to life; the texture may slightly change but still remains delicious!

Bumpy Cake is an enjoyable journey through classic flavors and a little creativity. With its delightful texture and fun presentation, it’s easy to see why this cake makes you smile! Don’t hesitate to play around with the toppings or flavors to make it your own—because baking is all about experimentation and making it uniquely yours. Gather your ingredients, and let this delicious cake fill your kitchen with warmth and joy. Happy baking!

Recipe FAQs

Bumpy Cake

Recipe Author: Linsey

Bumpy Cake offers an irresistible combination of flavors with its rich cocoa and coffee base, topped with creamy buttercream and fudge frosting. This delightful dessert is perfect for sweet cravings and gatherings, delighting everyone with its homemade goodness.

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• Prep Time 25 minutes
• Cook Time 140 minutes
• Yield 15 servings 1x

Ingredients

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• 1/2 cup 2oz, 60g unsweetened cocoa powder
• 1 1/2 teaspoons baking soda
• 1/2 teaspoon table salt
• 1/2 cup 4fl.oz, 125ml brewed coffee hot
• 1/2 cup 4fl.oz, 125ml vegetable or canola oil
• 1 cup 8fl.oz, 250ml buttermilk
• 2 teaspoons vanilla extract
• 2 eggs room temperature
• 1 3/4 cups 12.3oz, 350g granulated sugar
• 2 cups 10.6oz, 300g all purpose flour
• 6 tablespoons unsalted butter softened
• 1/8 teaspoon table salt
• 2 cups 9.2oz, 260g powdered sugar
• 1 teaspoon vanilla extract
• 1-2 tablespoons buttermilk
• 1/2 cup 4fl.oz, 125ml buttermilk
• 2 tablespoons corn syrup
• 1/2 cup 2oz, 60g unsweetened cocoa powder
• 1/2 cup 4oz, 115g unsalted butter
• 1/4 teaspoon table salt
• 4 cups 18.3oz, 520g powdered sugar
• 1 teaspoon vanilla extract

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Instructions

1. Prep the oven by preheating it to 350°F (177ºC) and spraying a 9×13-inch cake pan with nonstick spray. Set aside.
2. In a mixing bowl, combine cocoa powder, baking soda, and salt. Add hot coffee and mix gently for about 15–20 seconds until smooth.
3. Incorporate the oil and buttermilk, mixing until well combined. Beat in vanilla and eggs on medium speed until smooth, around 1–2 minutes.
4. Add granulated sugar and flour, mixing on medium speed just until smooth. Expect a thinner consistency for the batter.
5. Pour the batter into the prepared pan and bake for 30–35 minutes. The cake is done when the center springs back and a toothpick comes out with a few moist crumbs.
6. Allow the cake to cool in the pan for 20–30 minutes, then transfer it to the freezer and chill for 20 minutes.
7. While chilling, beat butter on high speed until creamy. Add salt, powdered sugar, vanilla, and one tablespoon of buttermilk, mixing from low to medium-high until fluffy. Adjust with additional buttermilk if needed.
8. Fill a piping bag with the buttercream and pipe thick ridges across the short side of the cake, leaving some space between each row.
9. Freeze the cake again for about 40 minutes until the buttercream ridges firm up.
10. In a saucepan, combine buttermilk, corn syrup, cocoa powder, butter, and salt over medium-low heat. Stir until the butter melts and mixture bubbles slightly.
11. Remove from heat and whisk in powdered sugar and vanilla until smooth and glossy. Allow to cool slightly before frosting.
12. Pour the warm fudge frosting over the cake, ensuring the buttercream ridges are covered. Tilt the pan to spread evenly without a spatula.
13. Refrigerate until frosting is set, then let slices sit at room temperature for 15–20 minutes before serving.

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Notes

For added flavor, consider substituting coffee with espresso.
If the cake is too thick, you can add a little more buttermilk to achieve the desired consistency.
Let the cake cool completely before frosting to prevent melting.

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Nutrition

• Serving Size: 1 slice
• Calories: 400
• Sugar: 36g
• Sodium: 300mg
• Fat: 18g
• Saturated Fat: 8g
• Unsaturated Fat: 8g
• Trans Fat: 0g
• Carbohydrates: 54g
• Fiber: 2g
• Protein: 3g
• Cholesterol: 60mg

Nutritional information is an estimate. The nutritional values for your final dish may vary based on measuring differences and products used.

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