Bumpy Cake is a chocolate cake that is topped with ribbons of vanilla buttercream and covered in chocolate ganache. The cake gets its name from the “bumps” that are created by the frosting when it is spread on top of the cake.
This recipe is in partnership with Imperial Sugar. CLICK HERE for the full recipe!
Bumpy Cake is a classic dessert that originated in Detroit, Michigan. It is a rich Devil’s Food cake that is topped with a rich, buttery vanilla frosting and covered in a thick layer of chocolate ganache. The cake gets its name from the “bumps” that are created by the frosting when it is spread on top of the cake.
Bumpy Cake was created by the Sanders Candy Company, which was known for its delicious chocolates and desserts. Rumor has it that the company’s founder, Fred Sanders, ran out of vanilla frosting one day, so he piped on what he had and poured chocolate ganache on top to cover the cake, creating the bumps you see. The cake turned out to be a hit, and it’s still sold to this day! I don’t know if this is true, but it’s a good story!
Special Tools You May Need
Beyond the obvious, a 9×13, a stand mixer etc, there are a few tools that will help make the process easier!
- A piping bag. And if you have a large round piping tip, even better! But just a bag will do because you can snip off the end of the bag, creating a round opening. If you don’t have piping bags, you can do this with a zip-top bag as well!
- An offset spatula. This isn’t totally necessary, but it always makes spreading that chocolate fudge frosting easier. If you don’t have one I highly recommend picking one up.
- A whisk. This isn’t really “special”, but it really helps make that chocolate ganache icing you pour on top smooth!
For the full recipe and ingredients list CLICK HERE!
- All-purpose flour
- Granulated sugar
- Unsweetened cocoa powder
- Baking powder
- Baking soda
- Canola oil
- Vanilla extract
- Brewed coffee
- Powdered sugar
- Vanilla extract
- Dutch process cocoa powder
- Heavy whipping cream
- Light corn syrup
- Sifted powdered sugar
How to Make This Bumpy Cake Recipe:
- Cake: Preheat the oven to 350° F. Coat a 9×13 inch baking pan nonstick spray, set aside.
- In the bowl of your stand mixer fitted with the paddle attachment, add in the flour, sugar, cocoa powder, baking powder, baking soda and salt. Mix together on low speed until combined.
- With the mixer still on low add in the eggs, buttermilk, oil, and vanilla, mixing until just combined, scraping the sides of the bowl as necessary. Slowly stream in the coffee and mix until smooth and combined.
- Pour the cake batter into the prepared pan and bake for 25 – 30 minutes, until the center is set and a toothpick inserted in the center comes out clean.
- Place the cake pan on a wire cooling rack and allow it to cool completely. Level the top of the cake with a serrated knife, if it domes when it bakes, so the top is flat.
- Vanilla Frosting: In the bowl of your stand mixer fitted with the paddle attachment mix the butter until smooth on medium speed. Add in the powdered sugar and 1 tablespoon of milk and continue mixing for 2 minutes until creamy, scraping the sides of the bowl as necessary, adding more milk if the frosting is too stiff.
- Place the frosting in a piping bag with a 1- inch round tip, or simply snip the bottom of the bag with scissors. Pipe the frosting into long tubes width-wise across the cake about 1 inch apart. Place the cake in the freezer while you prepare the chocolate icing.
- Chocolate Icing: In a medium saucepan over medium-low heat, melt together the butter, cocoa powder, heavy cream, and corn syrup. Bring the mixture to a boil and whisking constantly boil for 2 minutes. Slowly add in the powdered sugar, continuing to whisk until combined. Continue to cook and whisk for 4 – 5 minutes until the mixture is smooth and glossy. Remove from the heat.
- Transfer the icing into a glass bowl and allow it to cool for 10 – 15 minutes, whisking frequently, until it is warm, but not hot.
- Remove the cake from the freezer and pour the chocolate icing on top, coating the vanilla frosting first, and then carefully filling in the rest of the top of the cake, spreading it gently if needed, careful not to disturb the vanilla frosting. All the chocolate icing to set before serving.
Tips To Success:
- Use high-quality cocoa powder: The chocolate flavor is the star of Bumpy Cake, so it’s important to use a high-quality cocoa powder for the best flavor. I recommend using Dutch process cocoa powder, or even Hershey’s Dark cocoa powder.
- Make sure the cake is completely cooled before adding the vanilla frosting: If the cake is still warm, the frosting will melt and lose the round tubes of icing you want to achieve the bumps. Chilling the cake before adding the ganache ensures that the buttercream bumps hold their shape when you spread on the warm chocolate icing. And since the cake is chilled too it will help the chocolate to set up quicker.
- Use a warm knife to cut the cake: This will help create clean slices and prevent the cake. You don’t have to do this, but a knife run under hot water will slice through easier. Just dry off the water and wipe it off in between each slice.
Does Bumpy Cake need to be refrigerated?
Bumpy Cake is traditionally served chilled. You absolutely don’t have to chill it, but for authenticity, it’s recommended. I actually don’t prefer chilled cake, so I keep mine at room temperature and it’s totally fine, but that’s just me!
Love Chocolate Cake? Here Are A Few More Recipes To Try: