Bumpy Cake

How about a chocolate cake like no other? Bumpy Cake is a decadent chocolate cake layered with thick stripes of vanilla buttercream and covered in glossy fudge icing.

Those “bumps” aren’t just for show. They create pockets of sweet cream in every bite, adding texture and flavor you won't get from a traditionally frosted cake.

Then you have the fudgy topping setting into a soft shell, giving you another rich layer that contrasts with the buttercream and cake beneath.

Together, they create the perfect balance of creamy, cakey, and chocolatey in one decadent forkful. Need I say more?

What is Bumpy Cake?

Bumpy Cake is a rich chocolate cake topped with thick stripes of vanilla buttercream and coated in fudge icing.

It all started over 100 years ago when Fred Sanders, founder of Sanders Confectionery, ran out of buttercream for his devil’s food cake. He piped thick rows across the cake instead, then covered the whole thing in chocolate fudge. 

The result? Sweet vanilla “bumps” tucked under a glossy fudge topping, all layered over moist chocolate cake. 

Key Ingredients

For the Chocolate Cake:

• All-Purpose Flour: Measure it accurately for the best results. Use a kitchen scale or use the spoon-and-level method. Spoon the flour into your measuring cup, then level it off with a knife.
• Baking Soda: Make sure it’s fresh so your cake rises properly. To test it, drop a little of it into vinegar. If it bubbles right away, you’re good to go.
• Unsweetened Cocoa Powder: Use natural (not Dutch-processed) cocoa for that deep, old-fashioned chocolate flavor.
• Granulated Sugar: Besides sweetening, sugar helps keep the cake moist and tender after baking. That said, don't cut back on the amount in the recipe.
• Unsalted Butter: Use softened butter for easy mixing. If you didn't take it out ahead of time, pop it in the microwave for 5 to 10 seconds just until soft, not melted.
• Eggs: They should be at room temperature so they mix in better. If you forget, just let them sit in a bowl of lukewarm water for 5-10 minutes.
• Vanilla Extract: Adds a warm, sweet flavor that complements the chocolate. You’ll also need vanilla for the buttercream and the fudge icing.
• Buttermilk: Adds moisture and a slight tang that makes the cake tender. No buttermilk? Just mix 1 tablespoon of lemon juice or vinegar with 1 cup of milk and let it sit for 5 minutes.
  Hot Water or Coffee: Either will work, but coffee intensifies the chocolate flavor beautifully. Make sure it’s hot so it blends smoothly and dissolves any lumps in the batter.

For the Vanilla Buttercream:

• Unsalted Butter: Use softened butter so it creams more easily and creates a smooth base.
• Vegetable Shortening: Use it to help the frosting hold its shape. It's especially important for piping those signature “bumps.”
• Powdered Sugar: Use sifted powdered sugar for a light, fluffy texture with no lumps.
• Heavy Cream or Milk: Add just enough to get the frosting to a smooth, pipeable consistency.

For the Fudge Icing:

• Heavy Cream: Makes the icing smooth, creamy, and easy to pour.
• Granulated Sugar: Make sure it fully dissolves while heating with the cream and butter for a shiny, smooth finish.
• Unsalted Butter: Cut it into pieces before melting so it combines evenly with the sugar and cream for a rich, velvety consistency.
• Unsweetened Cocoa Powder: Go for a good-quality cocoa for a bold chocolate flavor and that deep color.

How to Make Bumpy Cake

Don’t be fooled by the bumps. This cake is easier to make than it looks!

1. Combine dry ingredients. Combine dry ingredients in a bowl.

2. Cream the butter. In a separate bowl, beat butter and sugar, then whisk in eggs and vanilla. 

3. Combine wet and dry ingredients. Stir dry ingredients and buttermilk alternately into the butter mixture. Mix in hot water.

4. Bake. Pour the batter into a greased 9×13-inch pan and bake at 350 degrees for 30-35 minutes. Set aside to cool.

5. Make the Vanilla Buttercream. Beat butter and shortening. Beat in powdered sugar, then mix in vanilla, salt, and just enough cream to create a thick, pipeable consistency.

6. Pipe the frosting. Transfer the frosting to a piping bag with a large round tip. Pipe long, even bumps across the cooled cake. Chill the cake for 30 minutes.

7. Make the Fudge Icing. In a saucepan over medium heat, combine cream, sugar, butter, cocoa powder, and salt. Stir until thick. Remove from heat and stir in vanilla. Let cool slightly.

8. Pour the fudge. Pour cooled fudge over the cake, letting it flow over the bumps. Tip the pan gently to coat without spreading. Chill the cake until the icing is set.

9. Serve. Slice bumpy cake using a hot knife for clean edges. Serve and enjoy!

Tips and Tricks

These tips take your Bumpy Cake from good to next-level amazing.

• Measure the flour accurately. Spoon the flour into the measuring cup and level it off with the back of a knife. Don’t scoop straight from the bag, or your cake will be dry.
• No buttermilk? No problem. Just mix 1 tablespoon of vinegar or lemon juice with 1 cup of milk. Let it sit for 5-10 minutes, or until it curdles.
• Use coffee instead of hot water. The cake won’t taste like coffee; it’ll only enhance its chocolate flavor.
• Chill the cake before frosting. Let the cake cool completely, then chill in the fridge. This keeps the buttercream firm and prevents it from melting under the fudge icing.
• Don’t rush the fudge. Let the hot fudge cool slightly before pouring it over the buttercream bumps. Too hot, and it’ll melt the frosting.
• No piping bag? You can use a zip-top bag. Just snip off a corner and pipe away.
• Try other cake flavors. You can do the same “bumpy” technique with other cakes. Try it with vanilla, caramel, red velvet, or even carrot cake.

How to Store Bumpy Cake

To Store: Place cake in an airtight container. Store at room temperature for 4-5 days or in the fridge for up to a week.

To Freeze: Double wrap the whole cake or slices in plastic wrap and foil. Freeze for up to 2-3 months. Let it come to room temperature before serving.