Walnut Espresso Cake with Buttercream Frosting

It's the last cake of the year from Aleksandra Crapanzano's Gâteau: The Surprising Simplicity of French Cakes.  I chose to make her Walnut Espresso Cake with Buttercream Frosting.

Let me tell you why I chose this one.  It's a tender two-layer espresso cake that's topped with fresh walnuts, then slathered (yes, slathered) with incredible espresso-flavored buttercream frosting.  Oh, then topped with more fresh walnuts.

I had pinpointed this cake from the very beginning and it was on my list to make, so was happy to choose it for the last cake.

There are lots of recommendations and tips from Aleksandra and me for this cake, so hang on while I list them below.

One, of course, is have the butter and eggs at room temperature.  I make that my mantra now on every bake.  It keeps the butter/batter from curdling because of temperature differences.

Another thing she mentions specifically is to use unsalted European butter.  I always use salted American butter - just like it better - but went out of my way to get unsalted European butter for this one (Plugra was available in our store).

To tell the truth, I don't see much difference in the bake and I truly like to use salted butter better.  If you have a recipe call for unsalted butter and you do use salted, cut down just a bit on added salt.  (i.e., if it calls for 1 teaspoon of salt, I'll lower it to ¾ tsp).  Up to you.

This cake is really best on the day you bake it.  If you don't need it until later in the day or evening, after it's cooled wrap it in plastic wrap and leave it at room temperature until ready to frost.  

You will need to refrigerate the leftovers and you'll find that the cake texture isn't as soft and tender after being refrigerated.

This recipe calls for rum in the frosting, but I used a teaspoon of vanilla instead because I don't like rum flavor.  Except for LifeSavers Butter Rum candy.  Which I don't think they make any more.

Sorry, getting off topic now...

We enjoyed this cake.  Be sure and toast your walnuts.  It brings out the oils and flavor and is totally worth the trouble.  I told Bret I had to go toast my nuts and he giggled.  Men.

To toast walnuts:  put your walnuts on a sheet pan in a 250° oven.  Toss them after 5 minutes, then leave in another 5-7 minutes. 

Let them cool before you put on the cake.  I, in my wisdom, did not let them cool and what do you know?  They started melting the buttercream frosting.  Duh!

I'm sure going to miss these easy and delicious recipes, but hey, I still have the cookbook and am going to keep it on the front row of frequently used books.

If you enjoyed this Walnut Espresso Cake with Buttercream Frosting, be sure and try my Persimmon Spice Cake and Walnut, Pear and Espresso Cake.

Visit the other Cake Slice Bakers' December choices listed below the recipe!  A lot of good ones this month.

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Walnut Espresso Cake with Buttercream Frosting

Yield: 12

Prep Time: 25 minutes

Additional Time: 17 minutes

Cook Time: 17 minutes

Total Time: 59 minutes

Tender, low-profile cake loaded with freshly toasted walnuts and filled/topped with amazing espresso buttercream frosting.

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Ingredients

• 3 large eggs, room temperature
• ¾ Cup plus 1 tablespoon butter*, room temperature
• ¾ Cup plus 2 tablespoons (175g) light brown sugar
• 2 teaspoons vanilla extract
• 1 ½ Cups (180g) cake flour
• 2 ½ teaspoons baking powder
• ½ teaspoon fine sea salt
• 1 tablespoon espresso powder (or 1 ½ teaspoons coffee extract)
• Frosting:
• 1 Cup butter, room temperature
• 3 ½ Cups (400g) powdered sugar
• ¼ Cup espresso
• 1 teaspoon vanilla extract
• 40 walnut halves (or chopped)

Instructions

1. For the Cake: Preheat the oven to 350°. Spray two 8" cake pans (bottom and sides) with cooking spray. Line the bottoms of the pans with parchment paper and lightly spray the paper. (Or you can make it a one-layer cake in a 10-inch springform or cake pan.)
2. In a small bowl or a measuring cup with a spout, whisk the 3 eggs together until just combined.
3. Cream the butter and sugar together in a stand mixer until very pale and fluffy (3-5 minutes).
4. Add one-third of the eggs into the mixer and continue to beat. Add another third and incorporate completely again. Finish with the last third. Add the vanilla and mix until combined.
5. In a medium bowl, sift the flour, baking powder, salt and espresso powder together. Add the dry ingredients into the mixing bowl and fold in with a rubber spatula. Gently fold these dry ingredients in just until no streaks of flour remain (gently scraping the bottom to make sure all the flour is incorporated).
6. Divide the batter evenly between the two pans (or the one 10" pan) and smooth the tops gently. (The batter will be rather thick and the layers will be thin, but will puff up some on baking.) Bake for 18-22 minutes. Remove to a cooling rack, then after about 10 minutes, invert the cakes onto the rack to finish cooling. Allow to completely cool to room temperature before frosting.
7. For the Frosting: Using a stand mixer or handheld mixer, cream the butter for 1 minute. Add the powdered sugar and beat until creamy and smooth. Add the cooled espresso and vanilla and beat to combine. Frost the cake just before serving.
8. Level out the cakes if necessary (layers will only be about 1-inch-ish tall).
9. Place the cakes on a cake plate and ice the bottom layer will one-half of the frosting. Place walnut halves or chopped walnuts evenly around the layer. Cover with the second layer of the cake and frost the top. If you'd like divide the frosting so you can frost the sides, but not necessary. Sprinkle the top with the chopped walnuts or place the halves neatly around the top.
10. The cake is best within a few hours of frosting it. If you premake the cake for an occasion, frost it just before serving. Refrigerate the leftovers because of the buttercream.

Notes

*I generally use salted American butter in my bakes, but Aleksandra specifically recommended European butter (higher fat content) in this one, so I used Plugra unsalted.

Toast your nuts, toast your nuts, toast your nuts. It's worth it for the extra flavor! (see main post for instructions)

Being gentle with the batter will create a more tender cake.

The original recipe calls for 1-2 teaspoons of dark rum for the frosting, but I don't prefer rum (hate it), so used vanilla.

Nutrition Information:

Yield: 12 Serving Size: 1
Amount Per Serving: Calories: 274Total Fat: 22gSaturated Fat: 11gTrans Fat: 1gUnsaturated Fat: 9gCholesterol: 90mgSodium: 338mgCarbohydrates: 15gFiber: 1gSugar: 2gProtein: 4g

Nutrition Values are Approximate

Each month The Cake Slice Bakers are offered a selection of cakes from the current book we are baking through. This year it is Gâteau: The Surprising Simplicity of French Cakes by Aleksandra Crapanzano. We each choose one cake to bake, and then on the 20th - never before - we all post about our cake on our blogs. There are a few rules that we follow, but the most important ones are to have fun and enjoy baking & eating cakes!

Follow our Facebook, Instagram, and Pinterest pages where you can find all of our cakes, as well as inspiration for many other cakes. You can also click on the links below to take you to each of our cakes. If you have a blog and are interested in joining The Cake Slice Bakers and baking along with us, please send an email to thecakeslicebakers at gmail dot com for more details.

The Cake Slice Bakers also have a new Facebook group called The Cake Slice Bakers and Friends. This group is perfect for those who do not have a blog but want to join in the fun and bake through this book.

Traditionally our last bake for the year is free choice, and our choices for December 2023 were ~

Raspberry Clafoutis

Berry Cake