Chocolate Blackberry Cake

Sep 22

Chocolate Blackberry Cake – Dark chocolate cake layers with blackberry compote and blackberry buttercream.

Chocolate Blackberry Cake

I’ve been wanting to make a blackberry buttercream for the longest time! My Gluten Free Cake with Mixed Berry Compote and Buttercream is one of my all-time favorite cakes. I knew the format for the compote and frosting would work great with blackberries but I thought the cakes would be too similar if I did a vanilla cake with the blackberry buttercream.

Instead, I went the route of my Dark Chocolate Strawberry Truffle Cake and made my favorite chocolate cake layers. The pairing of the sweet blackberry buttercream with the bittersweet chocolate cake layers is so decadent!

Bake Even Strips

You’ll see below that these chocolate cake layers turned out extra fudgy. I think this happened because I used new bake even strips. They did help my cakes to bake a little more flat, but it took an extra 10 minutes to bake and they turned out more brownie-like. Not sure I’ll sue them again on this particular chocolate cake recipe.

Here’s a quick assembly video to help as well:



Chocolate Blackberry Cake

Dark chocolate cake layers with blackberry compote and blackberry buttercream.

Course Dessert
Cuisine Cake
Prep Time 1 hour
Cook Time 18 minutes
Total Time 1 hour 48 minutes
Author Courtney Rich



  • 1 3/4 cups  plus 2 tablespoons (225 g)  all-purpose flour
  • 2 cups  minus 2 tablespoons (375 g) granulated sugar
  • 3/4 cups (88.5 g) good quality dark cocoa powder
  • 2 teaspoons (8 g) baking soda
  • 3/4 teaspoon (3 g) baking powder
  • 1 teaspoon (5.6 g) kosher salt
  • 1 cup (240 g) buttermilk shaken
  • 1/2 cup (109 g) vegetable oil
  • 3 large eggs at room temperature
  • 1 teaspoon (4.2 g) pure vanilla extract
  • 1 cup (236.6 g) hot water


  • 3 cups (360 g) blackberries
  • 1/2 cup (100 g) granulated sugar
  • 1 tablespoon (8.12 g) cornstarch sifted


  • 2 cups 4 sticks (452 g) unsalted butter slightly chilled
  • 6 cups (750 g) powdered sugar measured and then sifted
  • 1/3 cup (77 g) strained blackberry juice from compote above
  • 3 tablespoons (43.3 g) heavy whipping cream
  • 1 teaspoon (4.2 g) vanilla extract
  • Pinch of salt
  • *This buttercream recipe makes enough to fill and cover your cake. If you want to add additional piping, you’ll want to make an extra 1/2 batch.



  1. Preheat the oven to 350 degrees F. Spray four 6-inch pans or three 8-inch round cake pans with nonstick spray. Line the bottom of each pan with parchment paper, then spray the pans again.
  2. Combine the flour, sugar, cocoa, baking soda, baking powder, and salt into the bowl of an electric mixer fitted with a paddle attachment and mix on low speed until combined.
  3. In another bowl, combine the buttermilk, oil, eggs, water and vanilla.
  4. With the mixer on low speed, slowly add the wet ingredients to the dry, scraping the bottom of the bowl with a rubber spatula.
  5. Pour the batter into the prepared pans and bake for 16-18 minutes.  
  6. Cool in the pans for 10 minutes, then turn them out onto a cooling rack and cool completely.
  7. Wrap in plastic wrap and chill until ready to use. You're still going to want to level your cake layers to ensure a completely even surface for frosting and stacking.


  1. Combine the blackberries and sugar in a medium saucepan over medium heat. Stir the mixture while bringing it to a boil and occasionally breaking up the berries to release their juices.
  2. Add the cornstarch.
  3. Let simmer for about 10 minutes until the mixture is reduced by half. (We're trying to reduce the amount of water and thicken the mixture.)
  4. Strain 1/2 cup of the mixture and reserve for frosting. Refrigerate the strained blackberry mixture and the remaining compote for at least 4 hours before using. 


  1. In the bowl of a stand mixer fitted with the paddle attachment cream the butter on medium speed for about 3 minutes, until the mixture is light and fluffy.
  2. With the mixer on low speed, slowly add the powdered sugar, followed by the blackberry juice, heavy cream, vanilla extract and dash of salt.
  3. Continue to beat the frosting on medium-high speed for an additional 5 minutes.    
  4. Before frosting your cake, mix the frosting by hand with a wooden spoon to push out the air pockets. This will also help the frosting pull back together if it looks separated from adding the blackberry juices.


  1. Spread a dollop of frosting on a cake board or cake plate to hold the first cake layer in place.
  2. Place the first cake layer, top side up, on the cake board and pipe a rim of blackberry frosting around the edges to act as a barrier to the compote. For the 6-inch round cake, spread about 1/4 cup blackberry compote on the cake layer. For an 8-inch cake, spread 1/2 cup blackberry compote on the cake layer.
  3. Top with the next cake layer and repeat step 2.
  4. Place the final cake layer top side down. Apply a thin layer of frosting around the entire cake to lock in the crumbs. Freeze the cake for about 10 to 15 minutes to set the crumb coat.
  5. If your frosting feels soft at this point, refrigerate it while the crumb coat sets.
  6. Continue frosting your cake, making sure to stir the frosting with a wooden spoon to push out any air pockets.
  7. If you're not serving within the day, you can freeze the cake in a cake box or container for up to a week - just make sure to remove the cake from the freezer about 6 hours before you plan to serve it.  

9 thoughts on “Chocolate Blackberry Cake

Leave a Reply

Your email address will not be published. Required fields are marked *

  1. I don’t usually put a little layer of buttercream down before I add the compote, but it does make sense.. wouldnt it make it to slippery? Please tell me why you do that!! Thank you Karen

    1. I do it so the filling doesn’t seep into my cake layers. I want it to be it’s own layer in the cake. If you pipe rim around the edge of the cake before placing a second cake layer on top, it will help prevent it from sliding around.

  2. Hey Courtney! It looks like you are putting fresh blackberries on top of the compote in the video? Is this correct?

  3. How deep are the 6inch tins? I own 6 inch round 3 inch deep. Would this recipe suit these tins? If so how many layers?