A Detroit favorite: Chocolate Bumpy Cake recipe
A Detroit favorite
When customers make up their own name for a dessert on the menu, you know you have a winner. The original Bumpy Cake—made from rich devil’s food cake, rows of buttercream frosting affectionately known as bumps, and chocolate ganache-like fudge icing—has been a tradition for over a century. Fred Sanders first opened Sanders Chocolates in Detroit on June 17, 1875, and created the now famous cake in 1913 when he expanded his Detroit-based business beyond chocolate candy and fountain counter specialties to include a bakery division. Because customers would repeatedly visit the shop and say “I want the cake with the bumps,” it quickly became known as Bumpy Cake.
The cake’s signature rows are made of thick, buttery frosting, sweetened with powdered sugar and condensed milk. The most difficult part of the cake to master, the pourable fudge icing, gives the signature rows their chocolate coating and takes this already rich chocolate cake to a deeper level, more likely to be marked as a cake for hardcore chocolate devotees. When people ask you what makes the dark and dense chocolate cake so good (and they will), tell them it’s the combination of buttermilk and coffee—two magical ingredients recognized for their ability to awaken the flavor of chocolate. They also assist in keeping this cake from becoming dry. Please keep in mind that while this cake isn’t terribly fancy, it does require quite a few steps, and a candy thermometer is needed to prepare the boiled icing. Although it’s not the prettiest cake in presentation (it can be downright unruly to get those fudge-covered rows to dry evenly), it has an irresistible flavor—and a name—that makes it memorable. Here’s the recipe as I make it.
Recipe adapted from Sanders Chocolates.
2 cups granulated sugar
2 cups all-purpose flour, sifted
1 cup buttermilk
½ cup hot black coffee
½ cup unsweetened baking cocoa, sifted
½ cup vegetable oil
2 teaspoons vanilla extract
1½ teaspoons baking soda
½ teaspoon salt
Preheat oven to 375°F and grease a 9×13-inch sheet pan.
In a large bowl combine coffee and cocoa; beat on medium speed for 30 seconds. Add each of the following ingredients and beat for 30 seconds between additions: oil, buttermilk, baking soda, salt, vanilla, eggs, and sugar. Add flour; beat for 5 minutes. Batter will be very bubbly.
Pour batter into prepared pan and bake at 375°F for 35–40 minutes.
3 cups powdered sugar, sifted
2 cups butter
2/3 cup sweetened condensed milk
2 large egg whites
½ teaspoon salt
½ teaspoon vanilla extract
Place butter in mixing bowl, add 2 cups powdered sugar, and mix at low speed to obtain the consistency of a smooth paste. Then whip at medium speed, adding milk slowly and gradually, until frosting becomes light and fluffy.
Using a very clean bowl and beater, whip egg whites until stiff, while slowly adding the 1/2 cup powdered sugar. Carefully fold this meringue into the butter mixture. Add vanilla and remaining 1/2 cup powdered sugar. This last amount of sugar can be doubled if a stiffer icing is desired.
Pourable fudge icing
2 1/2 cups powdered sugar
1 cup granulated sugar
1/2 pound butter, divided
1/2 cup buttermilk
1/3 cup dark corn syrup
1/3 cup unsweetened baking cocoa
1 teaspoon vanilla extract
1 dash salt
In a saucepan over medium-high heat, combine buttermilk, sugar, corn syrup, cocoa, salt, and half the butter. Bring mixture to a boil.
When the mixture reaches soft ball stage, remove from heat (Soft ball stage refers to a temperature of 235–240º with a sugar concentration of 85 percent. Use a candy thermometer for accuracy.)
Add remaining butter, powdered sugar, and vanilla. The fudge should now have a pourable consistency.
When cake is cool, place cake in freezer for at least 30 minutes.
Pipe prepared buttercream icing to shape 1-inch rolls onto the frozen cake, with each row 1-inch apart across the top of the entire cake. Return to the freezer for an additional 15–30 minutes.
Pour cooled fudge frosting on top of cake, covering buttercream rolls completely. Return to freezer for several minutes or more to set frosting before serving.
Happy cake baking!