Blueberry Layer Cake

No artificial coloring or dye here, these colors and flavor are all natural. A soft tender layer cake that tastes of wild blueberries, filled with a blueberry compote and wrapped in a sweet, blueberry buttercream. Fresh blueberries and freeze dried berries team up to turn this blueberry layer cake into a purple wonder. 

Fresh blueberry cake, a very blueberry cake  

I went back and forth on this one. I had the cake recipe perfected and I thought, I bet they (they being people who come across my content and tell me they don’t like blue food, lol) won’t like the color of the cake. Should I redo it? I could add food coloring and make it more purple… I could redo the recipe… find a way to omit the baking soda (which is the cause of the color of the cake, as it reacts with the blueberry puree). 

Ugh, but the filling was already made and the buttercream was perfect. And I took a bite of the cake and I thought, , this it actually tastes like real blueberries! I didn’t want to change anything about the ingredients… and altogether I thought it all looked so beautiful as it was without any artificial food coloring. 

Why this Blueberry Layer Cake is wonderful

A long time ago I told you about a blueberry ice cream which spurred a fascination with blueberries fully incorporated into baked goods. This cake was born of that latent obsession. 

The thing about most blueberry cake recipes is that they aren’t blueberry cakes… they are lemon cakes with blueberries added to them. Which is fine, if you want fruit bits in your cake, but I wanted the cake itself to  taste like blueberries! And I didn’t want lemon to overtake it, because it is often quite often more obvious when mixed with a berry. 

You are going to take a bite of this cake (after giving me a funny look about the color) and you’ll say, god damn this tastes like blueberries! We get this wonderful flavor by adding a blueberry reduction and blueberry powder (both easily made at home). Together they make for a really, really special cake. 

How to make the blueberry cake layers 

Let’s start with the blueberry puree, first you’ll add the berries to a pot and begin cooking. It’ll take about 20 minutes to get the berries to fully soften and burst. 

It isn’t just the softening that needs to happen but some of the water needs to evaporate too. Once all the berries have burst (you can help some of them along by pressing on them with the back of a spoon/spatula) keep cooking until the water level has visibly reduced. 

Once that’s done you can strain it to remove the skins, or you can keep them in. Just make sure you have 1/2 cup of the puree. Let it cool while you make the cake batter. 

Start by adding all the dry ingredients, including ground up freeze dried blueberries, to your stand mixer bowl. 

We’re doing a reverse cream for this cake batter, so all the dry ingredients and the butter get beaten together until the mix is ‘sandy’

Once you can’t spot any more big butter bits, then you can start adding eggs. Do it one by one, allowing each to incorporate before adding another. When it’s fully ‘whipped’ you can add the blueberry puree, and the buttermilk. 

The batter will be airy and light, a bit purple from the lemon juice too! Split it between two cake pans and bake. 

Blueberry Buttercream: All-Natural Blueberry Buttercream 

This is a really basic buttercream, the only thing we do is add some ‘blueberry powder’ to it (basically freeze dried blueberries processed and sifted to remove seeds). I’ve found that as the powder sits in the buttercream base it gets more and more potent in color and taste. So we’ll only add a little and we’ll do it ahead of time. It’s going to be great! 

I didn’t do it here but I KNOW it would be wonderful: add about 4 oz softened cream cheese to the buttercream (and skip the milk). Even with the cream cheese this will be fine to sit overnight at cool room temperature (the amount of sugar in it will keep it from spoiling). 

Do Ahead  

• Must do the night before: make the buttercream. This buttercream is made with freeze dried blueberries/blueberry powder and it gets more and more potent in flavor overnight. We’re only going to use a bit here, initially it will make the buttercream a light purple and have a hint of blueberry flavor. As it sits overnight, it gets more intense. When you stir it in the morning, you’ll see the color turn even more vibrant. 
• Do a few hours ahead: make the filling. It’s pretty simple, just cook some fresh berries with sugar and lemon for a few minutes until they get a bit soft. This needs to chill fully before it goes between the cake layers. You can do it the night before along

FAQ for Blueberry Layer Cake 

Where do I get freeze dried blueberries? 

Check the nuts and dried fruit section of the grocery store 

Can I skip the freeze dried blueberries? 

Nope! We use quite a bit of it in the cake and it’s the reason the buttercream looks the way it does and tastes of blueberries. Without it you’ll miss out on a ton of flavor. 

Can I use frozen blueberries to make blueberry layer cake? 

I think that will be fine. I personally like the flavor of wild blueberries but you’ll need to use more of them (and there will be lots of skins to sieve out for the puree that goes into the cake. 

Can I bake this in a different sized pan? 

You could possibly do this in three 6” round cake pans for a taller cake. Or a 13×9” cake pan. Bake times will differ, check for doneness by pressing the top to see if it springs back and is firm (or with a cake tester). 

Why should I use organic powdered sugar for the buttercream? 

First, organic has a hint of the natural sugar molasses in it so the sugar is tastier. But more importantly, look for a sugar that is made with tapioca instead of cornstarch. It simply tastes better! 

Blueberry Layer Cake Recipe 

Blueberry Layer Cake

Two layers of tender blueberry cake flavored with both freeze dried berries and fresh blueberries cooked into a compote. A reverse creaming method gives this an excellent tender crumb. Blueberry compote in between the cake layers and a blueberry buttercream, naturally flavored and colored turn this into a very blueberry cake.

5 from 5 votes

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Ingredients

Blueberry powder

• 2.4 oz or 108g freeze dried blueberries processed into a powder and sifted to remove seeds.

Blueberry Buttercream

• 226g or 1 cup butter softened
• 360g or 3 cups organic powdered sugar
• 1 teaspoon vanilla
• 1 teaspoon fine sea salt
• 1 tablespoon blueberry powder* from above
• milk as needed to make a smooth buttercream

Blueberry Filling

• 200g or 1 heaping cup blueberries
• 50g or ¼ cup sugar
• Zest of half a lemon
• 1 teaspoon lemon juice

Blueberry Cake

• 125g or ½ cup reduced blueberry puree*
• 300g or 2 ½ cups cake flour
• 2 teaspoons baking powder
• ½ teaspoon baking soda
• 1 teaspoon salt
• 170g or ¾ cup butter softened
• 300g or 1 ½ cups sugar
• 4 large eggs at room temperature
• 360g or ¾ cup lowfat kefir or buttermilk
• 3 tablespoons blueberry powder from above
• 2 teaspoons lemon juice freshly squeezed

Method

To make the buttercream (the night before):

• In the bowl of a stand mixer or with a hand mixer, beat together the butter, salt, vanilla and blueberry powder. Add the powdered sugar (sift it in if it’s lumpy) and beat to combine, at least 3 minutes, scraping the bottom and sides as needed. Add milk or heavy cream to the mix until you have a smooth buttercream. Place it in an airtight container and leave it at cool room temperature. The color will darken as the blueberry bits dissolve, after a few hours, stir it to get the color to smooth and intensify.

To make the filling:

• In a small pot, cook over medium heat all the ingredients together for about 15 minutes, until the blueberries soften and burst. Place in a container in the fridge. It will thicken as it cools.

To make the cake:

• Using a blender or food processor, puree 1 1/2 cups of fresh blueberries. Sieve the mixture to remove seeds and then cook it in a pot over medium heat, until it’s reduced, thickened and much of the water has evaporated. You can also cook the berries before pureeing. You’ll need ½ cup for the cake. Let it cool fully before adding to the cake batter.
• Preheat the oven to 325 F. Butter and flour two 8” round cake pans.
• In the bowl of a stand mixer fitted with the paddle attachment, beat together the butter, sugar, cake flour, baking powder, soda and salt until the mixture is fully combined and sandy.
• Add the eggs, one at a time, allowing for each to be fully combined before adding another. Once all four are in, let the mixture run for a few minutes, scraping the bottom of the bowl as needed.
• With the mixer on, slowly pour in the blueberry reduction, blueberry powder, lemon juice and kefir. Once the batter is fully mixed, divide it between the two cake pans.
• Bake until top is firm when pressed or a cake tester comes out clean, about 40 minutes.

Cake assembly:

• Stir the buttercream really well with a rubber spatula, you’ll see the color change as you do. Put it into a large piping bag (this will help you create ‘walls’ so that the filling doesn’t leak).
• Once the cakes have cooled, use a bread knife to slice off the tops of the cake domes. Pipe a border of buttercream around the top of one of the cakes. On the top of the other cake, spread a thin layer of buttercream.
• Spread the filling inside the buttercream border and place the second cake face down. Pipe the rest of the buttercream around the cake and on the top and smooth it around with an offset spatula.
• Get ready, blueberry heaven is about to happen.

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