Get ready to dive into light and fluffy cake layers, sweet and tart blackberry lime compote, and the deliciousness of fresh whipped cream and silky, smooth blackberry buttercream with my new Blackberry Lime Italian Soda Cake
Blackberry Lime Italian Soda Cake
This isn’t just any ol’ blackberry and lime cake! This Blackberry Lime Italian Soda Cake is something real special thanks to the blackberry lime compote and whipped cream filling. When you take your first bite, I know you’ll agree that adding a couple extra elements like these to the cake definitely give it that Italian soda vibe and take this cake to the next level!
We have my friend Abi Ayres to thank for the idea. A few weeks ago she posted a recipe for a blackberry lime Italian soda that made my mouth water! The flavors sounded amazing and you know I loved the idea of turning this springtime drink into a cake!
Blackberry Lime Cake
I love how light and fluffy these cake layers are. You’ll get a hint of lime from the lime zest, but it’s the texture I know you’ll love. It’s a tender and delicate crumb, that creates the perfect base for the more powerful blackberry lime compote and buttercream.
For the cake layers, you’ll want to have the following ingredients on-hand:
- Cake flour
- Baking powder
- Salt
- Limes
- Unsalted butter
- Granulated sugar
- Eggs
- Vanilla extract
- Buttermilk
How to Make a Moist Cake from Scratch
Don’t forget to follow my go-to tips for getting moist cakes that rise well:
- Preheat your oven for 30 minutes prior to baking.
- Use good quality pans like Fat Daddio.
- Spray your pans with nonstick spray and line with parchment paper.
- Make sure to beat the butter, sugar, oil and eggs really well. The mixture should be smooth in texture and nearly doubled in volume when you’re done mixing. THIS ONE IS IMPORTANT!
- Don’t overmix your cake batter once you add the dry ingredients.
- Use room temperature wet ingredients. Not cold at all.
- Use fresh baking powder.
- Bake until a toothpick inserted in the center of the cake comes out with a few moist crumbs on it. REMEMBER: the cake continues to bake for a few minutes while it cools in the pan.
How to Make Blackberry Lime Compote
The blackberry lime compote is super simple. You’ll be using fresh or frozen blackberries, granulated sugar, cornstarch, and lime zest. The goal is to simmer the mixture long enough that it thickens. You’ll know you’re at a good spot when the mixture coats a spoon well.
Can I make this ahead of time?
For sure! I actually prefer to make this ahead of time so the compote can cool and thicken a tad more.
How to Make the Best Buttercream Frosting
To get a light and fluffy homemade buttercream frosting, make sure you follow my tips over at: HOW TO MAKE THE BEST BUTTERCREAM
These steps are written up for my vanilla buttercream, but are supposed to be applied to any of my buttercream recipes.
- Sift your powdered sugar
- Use slightly cold butter – to soften the butter, turn your mixer to medium-high and beat the butter on it’s own for a few minutes
- Use heavy whipping cream
- Beat for 5 minutes
- Stir by hand
You’ll want to check out the post linked above for more details on each step.
How to Stabilize Whipped Cream to Fill a Cake
My favorite way to stabilize whipped cream is to add a tablespoon of E-Z Gel to the cream, powdered sugar, and vanilla as I start beating the mixture. It is SO easy!
You can also use gelatin, but just know it’s a little trickier to master. Liz Marek from Sugar Geek Show has a great video tutorial if you want to go this route.
Is this whipped cream stable enough to hold cake layers?
Yes, this buttercream is stable enough to use between cake layers. I still pipe a rim of buttercream around the edge of the cake to ensure stability.
Can I decorate the cake with whipped cream?
I wouldn’t recommend it. It definitely won’t be as smooth and easy to work with as buttercream.
Other Fruit-Filled Cakes You’ll Love
- Peach Crisp Cake
- Lemon Pistachio Cake
- Strawberry Lemonade Cake
- Lemon Bar Cake
- Blueberry Delight Cake
- Lemon Poppy Seed Cake
More Lime-Inspired Cakes to Try
Blackberry Lime Italian Soda Cake
Ingredients
FOR THE CAKE
- 3 cups (345 g) cake flour
- 1 tablespoon (14 g) baking powder
- 1 tablespoon lime zest
- 3/4 teaspoon (4 g) salt
- 1 cup (226 g) unsalted butter, at room temperature
- 1 3/4 cups (350 g) granulated sugar
- 6 egg whites, at room temperature
- 1 1/4 cup (240 g) buttermilk, at room temperature
- 1/4 cup fresh lime juice
FOR THE COMPOTE
- 3 cups (360 g) blackberries
- 1/2 cup (100 g) granulated sugar
- 1 tablespoon (8.12 g) cornstarch sifted
- zest of one lime
FOR THE BUTTERCREAM
- 2 cups (452 g) unsalted butter, slightly chilled
- 6 cups (750 g) powdered sugar, measured and then sifted
- 1/2 cup (115 g) strained blackberry compote, to remove any seeds
- 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 ½ batch.
For the Whipped Cream
- 1 cup (240 g) heavy whipping cream, cold
- 1/2 cup (62.5 g) powdered sugar, sifted
- 1/2 teaspoon (2.1 g) vanilla extract
- 1 tablespoon E-Z Gel
Instructions
FOR THE CAKE
- Preheat the oven to 325 degrees F. Spray three 8-inch round cake pans with nonstick spray. Line the bottom of each pan with parchment paper, then spray the pans again.
- Combine the flour, baking powder, lime zest, and salt into a medium mixing bowl and whisk to combine. Set aside.
- In the bowl of an electric mixer, combine the butter and the sugar. Beat until light and fluffy, about 3 to 5 minutes.
- Gradually add the egg whites, making sure to mix well between each addition, being sure to scrape down the sides and bottom of the bowl as you go along. Once all of the egg whites are added, mix for an additional 3 minutes, until the mixture is lighter in color and smooth in texture. You'll also notice the volume increases.
- While the butter, sugar, and eggs mix, stir together the buttermilk and lime juice.
- Turn the mixer to low speed. Alternately add the flour mixture and the buttermilk mixture, starting and ending with the flour mixture. Stir just until combined.
- Divide the pans evenly between the three cake pans, about 16 ounces in each pan. Bake the layers for 25 to 30 minutes, or until a toothpick inserted in the center of the cake comes out with a few moist crumbs on it.
- Allow layers to cool in the pans for about 15 minutes before inverting them onto cooling racks to cool completely. Wrap in plastic wrap and chill until ready to use. If you need to level the cake layers, be sure to do that BEFORE you freeze them.
FOR THE COMPOTE
- Combine the blackberries, lime zest, 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.
- Add the cornstarch.
- 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.)
- If needed, to remove any larger pieces of blackberries, you can puree the compote in a food processor or blender. Just be sure to let it cool a bit before you do.
- Strain ½ cup of the mixture and reserve for frosting. Refrigerate the strained blackberry mixture and the remaining compote for at least 4 hours before using.
FOR THE BUTTERCREAM
- 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.
- With the mixer on low speed, slowly add the powdered sugar, followed by the strained blackberry compote, heavy cream, vanilla extract, and pinch of salt.
- Continue to beat the frosting on medium-high speed for an additional 5 minutes.
- 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.
For the Whipped Cream
- Combine the heavy whipping cream, E-Z Gel, powdered sugar, and vanilla in a chilled stainless steel bowl. Beat the mixture with the whisk attachment until stiff peaks are formed. Refrigerate until ready to use.
ASSEMBLY
- Spread a dollop of frosting on a cake board or cake plate to hold the first cake layer in place.
- 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. Spread half of the whipped cream over the cake layer, followed by about ⅓ cup of the blackberry compote.
- Top with the next cake layer and repeat step 2.
- Place the final cake layer top side down. Apply a thin layer of buttercream around the entire cake to lock in the crumbs. Freeze the cake for about 10 to 15 minutes to set the crumb coat.
- Continue frosting your cake, making sure to stir the buttercream with a wooden spoon to push out any air pockets.
Is that supposed to be 1 cup of butter for the cake?
Yes I fixed it.
Hi Courtney,
As a beginner I have one question If I wanred to measure with grams and not cups which one I need to follow US measurment or metric one. As there are grams in US cups measurement also mentioned in brackets? As I see there is much diffrence between both grams measurement that is one in metric measurement and one in US customery mentioned in brackets.
Thank you in advance
Yay! I’m so excited for this cake! I’ve anxiously waiting for the recipe since you posted on IG!
I always wonder if I can use liquid egg whites in place of separated egg whites?
yes!
I’d like to make this recipe for my upcoming baby shower but want to use a white frosting for the cake. Do you think there would still be enough blackberry flavor if I use a vanilla buttercream?
Yes I think so!
I am planning to make this cake for a friend’s baby shower. I will not have access to E-Z Gel in time to make the cake and am wondering if I can add a whipping cream stabilizer (eg. the brand Whip It) instead? If not, do you have any other recommendations for how to thicken the whip cream without the EZ Gel?
Yes!
If I am using gelatin instead of E-Z gel(I couldn’t find any near me!) do I still do one tablespoon of the gelatin?? Or how much gelatin would I use for the whipped cream? Thanks!
Same amount!
Is the grams in buttermilk correct? One cup is typically 240 grams of liquid and the recipe says 1 and 1/4cups.
I have 1/3 compote left. I assume that is to go into the icing as my icing is light pink and yours is a deep purple?
Yes the recipe says the compote goes into the buttercream.
The Blackberry Lime Italian Soda Cake sounds amazing and I really want to try it. The recipe does didn’t include the Italian soda as an ingredient which you mention takes it to the next level! How much do we add and when and do we use plain soda? Looking forward to trying this!
It’s not in the cake. It was just the inspiration for the cake.
Think I’m going to make this for a friend’s engagement party! Any substitution ideas for the E-Z Gel?
My daughter taught me a trick as a substitute. She said to use 2-3 mini marshmallows with the whipping cream!