Blum's Coffee Crunch Cake

Blum's Coffee Crunch Cake.. a lemon and vanilla chiffon cake with an espresso infused whipped cream frosting and coated with an airy and crunchy coffee honeycomb-like candy.

Blum's was a small chain of bakery/soda fountain shops in California (based in San Francisco) that closed in the 1970s. Its most beloved menu item was this coffee crunch cake.

The bittersweet candy coating was evidently created when a confectioner made a candy-making error. Instead of ditching the candy, he smashed it and used it to coat a cake.

While the idea of lemon chiffon with a coffee flavored topping sounds kind of odd, it actually works! The candy on its own is kind of bittersweet, but when it's nestled in the sweet coffee flavored whipped cream, it mellows and adds just the right amount of texture to the cake. It's pretty spectacular.

The candy for this cake is made by adding baking soda to a mixture of sugar, coffee, and corn syrup that has been cooking on the stove until it reaches 310 degree. The mixture bubbles up a lot, so be sure to use a large saucepan. Even when you pour it out to cool, it continues to puff up.

You can make the candy for this cake up to two weeks in advance and keep it in an airtight container.

This is definitely a special occasion cake. 

The steps for making this cake:

1. Make the coffee candy and let it cool. Once it has cooled, break it up in a zip sealed plastic bag by gently smashing it with a rolling pin. 
2. Bake the chiffon cake. It's a single layer that you will slice in half when you are ready to frost the cake. I wrapped my baked cake in plastic wrap and froze it until I was ready to assemble the cake. 
3. Make the espresso whipped cream frosting and frost the cake. Once you have frosted the cake, stick it in the refrigerator for an hour to set the whipped cream, lest it collapse under the weight of the candy. 
4. Coat the cake with the coffee crunch candy and serve! 

Hints and Tricks: 

This recipe also calls for adding espresso powder to the whipped cream frosting. It's an amazing secret ingredient, but I've always struggled with the way it hardens into a solid mass in the cupboard. I tried everything, including saving those silica packets to keep this from happening. 

You can add it back to a coffee grinder to turn it back into a powder, but it's not the same. Finally, I discovered that keeping the instant espresso jar in the freezer keeps it powdery. 

I love whipped cream frosting, but it is tricky when you are planning ahead. To stabilize it, you can add some instant pudding powder or Intant Clear Jel along with the sugar. There is also a product called Whip It made specifically for stabilizing whipped cream. 

Coffee Break - More Recipes with Coffee:

• Blum's Coffee Crunch Cake from Karen's Kitchen Stories
• Caramel Latte from Art of Natural Living
• Chai Banana Bread from A Kitchen Hoor's Adventures
• Gingerbread Lattes from Hezzi-D's Books and Cooks
• New York Crumb Cake from That Recipe

We share Recipes From Our Dinner Table! Join our group and share your recipes, too! While you're at it, join our Pinterest board, too!

Blum's Coffee Crunch Cake

Yield: 12 slices

Author: Karen's Kitchen Stories

Prep time: 30 MinCook time: 1 HourInactive time: 3 HourTotal time: 4 H & 30 M

Blum's Coffee Crunch Cake.. a lemon and vanilla chiffon cake with an espresso infused whipped cream frosting and coated with an airy and crunchy coffee honeycomb-like candy.

Ingredients

For the Coffee Candy

• 1 1/2 cups sugar
• 1/4 cup brewed coffee
• 1/4 cup light corn syrup
• 1 tablespoon baking soda

For the Cake

• 1 cup sugar
• 142 grams (1 1/4 cup / 5 ounces) cake flour
• 1 1/2 teaspoons baking powder
• 1/4 teaspoon salt
• 5 large eggs (including 3 separated), room temperature
• 6 tablespoons unsalted butter, melted and cooled
• 2 teaspoons vanilla extract
• 1 teaspoon lemon zest plus 2 teaspoons lemon juice

For the Whipped Cream Frosting

• 2 cups heavy cream, cold
• 6 tablespoons sugar
• 1 tablespoon instant espresso powder
• 1 teaspoon vanilla extract

Instructions

To Make the Coffee Crunch Candy

1. Line an 8 inch square cake pan with parchment paper and spray the parchment with spray oil. The parchment should go up the sides of the pan and have an overhang.
2. In a large saucepan over medium-high heat, heat the sugar, coffee, and corn syrup, stirring occasionally. Cook until the mixture reaches 310 degrees F. Add the baking soda and stir. The mixture will puff up, which is why you are using a large pan. Pour the mixture into the cake pan. Let cool completely.
3. Place the hardened block into a zip-loc bag and close the "zipper." With a rolling pin, crush the candy into bite-sized pieces.

To Make the Cake

1. Heat your oven to 325 degrees F with a rack set at the lower middle position.
2. Spray or grease a 9-inch cake pan, line the bottom with parchment, and spray or grease and the parchment. Dust the parchment paper and sides of the pan with flour. Reserve 3 tablespoons of the sugar.
3. In a large bowl, whisk together the flour, baking powder, salt, and the rest of the sugar. Whisk in two eggs, three egg yolks, melted butter, vanilla, lemon zest, and lemon juice until smooth.
4. It the bowl of a stand mixer with the whisk attachment, whisk the remaining three egg whites on medium-low for about a minute, until foamy. Continue mixing on medium-high until you have soft peaks, about another minute or two.
5. Fold 1/3 of the egg whites into the flour mixture. Once incorporated, gently fold the rest of the egg whites into the bowl until just combined.
6. Pour the batter into the pan and bake for 30 to 40 minutes, until a toothpick comes out clean. Cool in the pan on a rack, then turn the cake out onto a wire rack to cool completely.

For the Whipped Cream Frosting and Assembling the Cake

1. In the bowl of a stand mixer, whip the cream, sugar, espresso powder, and vanilla on medium-low for one minute. Increase the speed to medium-high and and whip until you have stiff peaks.
2. Cut the cake into 2 layers using a long serrated knife. Place one layer on your cake platter and spread 2 cups of the whipped cream over the top. Place the second layer on top of the first, and spread the rest of the whipped cream over the top and sides of the cake. Gently press the candy into the sides and top of the cake. Serve.

Nutrition Facts

Calories

466.12

Fat (grams)

22.34

Sat. Fat (grams)

13.4

Carbs (grams)

63.46

Fiber (grams)

0.28

Net carbs

63.17

Sugar (grams)

54.46

Protein (grams)

5.3

Sodium (milligrams)

147.98

Cholesterol (grams)

137.37

https://www.karenskitchenstories.com/2018/09/blums-coffee-crunch-cake.html

Karen's Kitchen Stories

Cake, Blum's Coffee Crunch

Dessert

American

Did you make this recipe?

Tag @karenskitchenstories.com on instagram and hashtag it # karenskitchenstories

Recipe adapted from The Perfect Cake: Your Ultimate Guide to Classic, Modern, and Whimsical Cakes.  There are over 240 recipes!!

First posted September, 2018 and updated January, 2023.