Blackberry Peach Cinnamon Cake

Preparation

For the Cinnamon Cake

Step 1
Preheat oven to 350°F. Grease 3, 8-inch cake pans and line them with parchment rounds.

Step 2
Add the unsalted butter and granulated sugar into the bowl of a stand mixer. Beat on a high speed with a whisk attachment for a few minutes, scraping down the sides of the bowl as needed with a rubber spatula. The mixture will become lighter in color as air is whipped into it.

Step 3
Add the egg whites and mix at a medium speed until they’re incorporated.

Step 4
Sift the dry ingredients (cake flour, baking powder, ground cinnamon and salt) into a separate bowl. Add half of the dry ingredients into the butter mixture, and mix on a low speed until just incorporated.

Step 5
Add the sour cream, vanilla extract, and oil, and mix at a low speed until combined, scraping the sides and bottom of the bowl as needed.

Step 6
Mix in the remaining dry ingredients on a low speed.

Step 7
Pour the batter evenly between the prepared cake pans. Chelsey likes to use a digital kitchen scale to weigh her pans, to make sure the layers will be the same height.

Step 8
Bake for 31-34 minutes, or until a toothpick comes out with a few moist crumbs. Rotate pans halfway through to help them bake evenly.

Step 9
Allow the pans to cool for 10 minutes, then run an offset spatula around perimeter of the pan to separate the cake from the pan and flip the layers onto a wire rack to finish cooling.

Step 10
Once the cake layers have fully cooled, use a serrated knife to level the tops and then cut each cake layer in half horizontally, so that you have six thin cake layers.

For the Blackberry Peach Buttercream Frosting

Step 1
While the cake layers bake and cool, make the blackberry peach buttercream frosting.

Step 2
Beat the butter on a medium speed for 30 seconds with a hand mixer or stand mixer fit with a paddle attachment until smooth.

Step 3
Mix in the vanilla extract and salt on a low speed until incorporated.

Step 4
Slowly add in the powdered sugar. Add in the heavy cream half way through to make the frosting easier to mix.

Step 5
Continue to mix until the ingredients are fully incorporated, and the desired consistency is reached. Place 1/2 cup of the plain vanilla buttercream into a small piping bag fit with a small French tip and set aside – this will be used to decorate the sides and top of the cake later in the process.

Step 6
Mix the blackberry jam and peach preserves into the remaining buttercream.

Step 7
If the frosting is too thick, add in additional cream (1 Tbsp at a time). If the frosting is too thin, add in more powdered sugar (¼ cup at a time).

Step 8
Stir by hand with a rubber spatula to make the frosting extra smooth. Place 1 cup of frosting in a small piping bag fit with a round piping tip, then cover the remaining frosting with plastic wrap and set aside.

For the Assembly

Step 1
Stack and frost cake layers on a greaseproof cake board, using a dab of frosting to help stick the first cake layer to the board.

Step 2
Spread an even layer of blackberry peach buttercream on top of the first cake layer. Pipe a ring around the cake layer to act as a frosting dam to keep the filling in place.

Step 3
Carefully spread 2 Tbsp of the blackberry jam on top of the frosting and top with a 1/3 cup of fresh blackberries.

Step 4
Repeat this process with the 2nd cake layer, but use 2 Tbsp of peach preserves and top with 1/3 cup of diced peaches.

Step 5
Chill the cake in the freezer for 5 minutes once the two layers are stacked to help lock the filling in place and make it easier to stack the remaining cake layers.

Step 6
Repeat this process with the remaining cake layers.

Step 7
Once all the cake layers are stacked, spread a thin coat of blackberry peach buttercream around the cake to fully cover the cake layers.

Step 8
Smooth using a bench scraper, then chill the cake in the fridge (30 minutes) or freezer (10 minutes) until the frosting is firm to the touch.

Step 9
Add a second, thicker layer of buttercream to the cake, and smooth using a bench scraper.

Step 10
Divide the remaining buttercream into three bowls, and color 3 different shades of purple using gel food coloring.

Step 11
Decorate as desired! Chelsey chose to add a textured look with the reserved white frosting and the ombre purple buttercream, and decorated the top of the cake with buttercream dollops and fresh blackberries.

Notes

◦ Be sure to properly measure your flour (spoon into the cup measure, then level) or use a kitchen scale.

◦ Make sure your ingredients are at room temperature to help them mix together better.

◦ Don’t overmix your batter, stir until the flour is just combined.

◦ Don’t level and torte your cake layers until they are completely cooled.

◦ Pipe a ring of buttercream around each cake layer before adding the jam and fresh berries. It will act as a frosting dam and keep all that delicious filling in place.

◦ If you have a lot of fresh or frozen blackberries on hand, make Chelsey’s homemade blackberry freezer jam! It’s absolutely delicious and makes a wonderful cake filling.

◦ Make sure your buttercream is the right consistency. This will help give your cake proper structure and make it easier to decorate.

◦ If your cake layers turn out less than perfect, read Chelsey’s cake troubleshooting guide to see where things might’ve gone awry.

Tips

◦ Make your cake layers in advance and freeze them. It breaks the process up and make it more approachable.

◦ Make your frosting ahead of time too, or save any leftover frosting! It can be stored in an airtight container in the fridge for up to a month, or in the freezer for up to 3 months. Be sure to give it a good stir once it thaws to get the consistency nice and smooth again.

◦ This blackberry cake filling can be made up to two weeks in advance if stored in an airtight container in the fridge.

◦ A frosted cake can last in the fridge for up to a week, or in the freezer for up to a month. The buttercream locks in all the moisture, keeping the cake fresh and delicious!

◦ If you cut into the cake and have leftovers, use any remaining frosting to cover the cut section to keep it moist and store in the fridge for up to a week.