A Cake Recipe for the Atomic Age: Following the Story of a Unique Cake on Chicago’s South Side

When was the last time you had an atomic cake? If you are on the south side, probably quite recently. The hyperlocal cake is famous in the region and loved by people who have eaten it.

Typically, it’s constructed like this: banana cake on the bottom, topped with Bavarian cream, sliced ​​bananas and whipped cream; then chocolate cake topped with strawberry frosting, sliced ​​strawberries and whipped cream; then yellow cake topped with a layer of fudge, and the whole cake topped with whipped cream. The fudge layer can shift, as can the chocolate cake layer, layers of whipped cream are sometimes omitted, and sometimes the sides are bare and other times they are completely covered.

Kim Goebel, the president of La Petite Pastry in Chicago’s Clearing neighborhood, says the cake has a mysterious background.

“I don’t know who started [making the cake]she said, noting that at La Petite Pâtisserie they actually call it “rainbow cake.”

“I started working in the bakery in 1973, and they were already there,” says Goebel. “My husband started the business in 1967, and he’s been doing it since he started.”

You’ll get this answer from many bakeries that sell it: they don’t know where it comes from, but they can’t remember. not be on the menu. Some believe it may be a product of the Baker’s Dozen, a secret society of non-competitive Chicagoland bakers who have been meeting since the 1930s. Others claim to have invented it themselves, with bakery advertisements history flooded with claims of “inventor of the atomic cake”. In reality however, the origin of the cake goes back to two bakeries: Calumet and Liberty. And the real inventor? Georges Kremm.

An atomic cake from Weber’s Bakery. Credit: Jennifer Billock

Baker George Kremm worked at the Calumet Bakery in South Deering in the 1940s and 1950s, at the height of the atomic age. Kremm created a cake to honor the era while working at Calumet, naming it the Atomic Cake. But he didn’t sell the cake there. Instead, Kremm left Calumet Bakery to open his own shop, Liberty Bakery, in Roseland in the 1950s. There he started his cake. The two bakeries claim the title of inventor, since the cake was imagined in Calumet but brought into the world in Liberty. It only adds to the later confusion that Liberty is now closed, Calumet is famous for its atomic cake, and so many other places claimed to invent it when the cake first surfaced.

An even deeper mystery about atomic cake is why it’s popular almost exclusively on the South Side, where you can find it in the checkout of nearly every bakery and on the table at nearly every celebration. Everyone knows the atomic cake. It is almost the bestseller of all bakeries. In fact, the cake is so ubiquitous in the neighborhood that some bakers don’t even know it’s not sold anywhere else in town. Goebel was surprised to hear so much. But in the north, unless you talk to a baker or a transplanted resident, you’ll get blank stares. That’s not to say bakeries haven’t tried to sell it, though.

“There was a bakery on the north side, Gladstone Park Bakery, which was almost our version on the north side,” Weber’s Bakery owner Mike Weber said in an interview for my book, Historical Chicago Bakeries. “They were like a mirror. [The owner,] Dean Hedeker said to my dad, “Well, I can’t sell this atomic cake here.” But he could do it as well as us.

Some bakeries sell Atomic Cakes on the North Side only by special order, but it’s a relatively unknown dessert there. No one I’ve asked – about 10 different bakers – knows why.

“It’s really Chicago,” says Goebel. “It’s a Chicago thing. I have relatives in Colorado and I tried to call a bakery there to tell them to make this and they were like, ‘Banana cake? What is banana cake? »

So why have so many bakeries claimed to invent it, leaving the origins of the cake obscure to those who ask? Because practically every bakery has its own version. La Petite’s Rainbow Cake contains whipped cream, a thin layer of fudge, yellow cake, fresh strawberries, chocolate cake, fresh bananas and banana cake, and all the whipped cream pure between the two. The sides are left uncovered, but the top has a colorful swirl of whipped cream.

Weber’s version of the Atomic Cake is called the Split Banana. The top and bottom cakes are banana, omitting the yellow cake altogether. The sides are left uncovered here too. Other bakeries cover everything with whipped cream and some use buttercream. Some bakeries call it a bomb cake instead of an atomic cake.

“People make them all different,” Goebel said. “Some don’t have bananas, others alternate where the chocolate cake goes with the chocolate fudge.”

Sometimes it’s not even the traditional round cake. Goebel sells a round cake, a sheet cake version, and a perfect version. Orland Park Bakery sells Atomic Cake Paczki. Other bakeries sell atomic cupcakes and atomic donuts, and an enterprising burger joint once sold an atomic cake burger. But one thing you’ll probably never find is the cake sold in one slice. Fresh bananas turn brown after you cut a slice, and no one wants to buy a slice of cake featuring golden bananas.

The next time you indulge in an atomic cake, know that you’re dining on a complicated yet delicious baking story in Chicago.

Adapted from the rainbow cake recipe from La Petite Pâtisserie

Note: Feel free to use more or less toppings and whipped cream. It all depends on your taste preferences! You can also use store-bought bavarian cream, strawberry icing, and chocolate fudge for convenience, but take the time to make fresh whipped cream, it’s worth it.


1 prepared 9-inch round banana cake (ingredients below)
2 bananas, sliced
1 cup Bavarian cream (ingredients below)
1 prepared 9-inch round chocolate cake (ingredients below)
1 cup strawberries, sliced
1 cup strawberry frosting
1 prepared 9-inch round yellow cake (ingredients below)
1/2 cup chocolate fondant (ingredients below)
3 cups whipped cream (ingredients below)

For the banana cake:

2 cups flour
1 1/4 cup sugar
1 teaspoon baking soda
1/2 teaspoon of salt
3 ripe bananas, mashed
3/4 cup buttermilk
1/2 softened butter
1 teaspoon vanilla
2 eggs, room temperature

For the chocolate cake:

1 cup unsweetened cocoa powder
2 cups flour
1 teaspoon baking soda
1 1/2 teaspoon baking powder
1 teaspoon of salt
2 cups of sugar
3 eggs, room temperature
3/4 cup butter, softened
1 1/2 cup milk
2 teaspoons vanilla

For the yellow cake:

2 1/2 cups flour
1 2/3 cup sugar
2 1/2 teaspoons baking powder
1/4 tsp salt
3/4 cups butter, softened
3 eggs, room temperature
1 1/4 teaspoon vanilla
1 1/4 cup milk

For the Bavarian cream:

1/2 tablespoon powdered gelatin
2 tablespoons cold water
1 egg yolk
1 1/2 tablespoons sugar
1/2 cup half and half
1/2 cup heavy cream

For the strawberry frosting:

1 pound strawberries, hulled and chopped
1 1/2 cups white sugar
1 tablespoon lemon juice

For the chocolate fondant:

3/4 cup sweetened condensed milk
1/2 cup semi-sweet chocolate chips
1 tablespoon of butter

For the whipped cream:

1.5 cups heavy whipped cream
1 tablespoon powdered sugar
1 teaspoon vanilla (optional)


1. Prepare the banana cake. Preheat oven to 350. Grease and flour a 9 inch round cake pan. Mix all the dry ingredients. Add bananas, buttermilk, butter and vanilla. Mix until homogeneous. Add the eggs. Mix until homogeneous. Transfer the batter to the skillet and bake for 25-30 minutes, until a toothpick comes out clean. Once cooled, cut the top so that it is flat.

2. Make the chocolate cake. Preheat oven to 350. Grease a 9 inch round cake pan and line the bottom with parchment paper. Mix all the dry ingredients. Add the remaining ingredients and mix well. Transfer the batter to the skillet and bake for 30 minutes or until a toothpick comes out clean. Once cooled, cut the top so that it is flat.

3. Prepare the yellow cake. Preheat oven to 350. Grease and flour a 9 inch round cake pan. Mix all the dry ingredients. Add the remaining ingredients and mix well. Transfer the batter to the skillet and bake for 20 to 25 minutes or until a toothpick comes out clean. Once cooled, cut the top so that it is flat.

4. Prepare the Bavarian cream. Mix the gelatin in the water and let it swell. Meanwhile, whisk egg yolk and sugar until fluffy. Heat half and half in a small saucepan over low heat until boiling. Temper the egg mixture with the hot half and half, then pour the egg mixture into the pan while stirring. Continue boiling for 3 more minutes. Remove the custard from the heat, stir in the gelatin and let cool. Meanwhile, whip the cream until stiff. Once the custard has cooled, fold it into the whipped cream. Cover and refrigerate until set, about an hour.

5. Prepare the strawberry frosting. Add strawberries and sugar to a saucepan. Bring to a boil over medium-low heat. Add lemon juice and continue to boil and stir until thickened, about 10 to 15 minutes. Blend the jam with an immersion blender until smooth. Cook for a few more minutes, then let cool.

6. Make the chocolate fondant. Combine all ingredients in a double boiler and beat until chocolate is melted and sauce is smooth.

seven. Make the whipped cream. Combine all ingredients and mix with a stand mixer or hand mixer until whipped cream has stiff peaks. Cover and store in the refrigerator until needed.

8. When the cakes are cool, build the atomic cake: Put the banana cake on a plate. Pipe a ring of whipped cream around the edge, about 1 inch high. Garnish in the middle with Bavarian cream. Spread the banana slices over the Bavarian cream. Put the chocolate cake on it. Pipe a ring of whipped cream around the edge, about 1 inch high. Fill the middle with strawberries. Spread the strawberry frosting over the strawberries. Pipe a point of whipped cream in the centre. Put the yellow cake on top. Spread a thin layer of fudge on the yellow cake. Spread whipped cream on top, about 1 inch high, and decorate however you like. Leave the sides of the cake bare.

9. Refrigerate cake for at least 30 minutes before serving to allow layers to firm up.