Easy lemon and blackberry cake starts with moist blackberry cake with lemon zest, and has an easy blackberry cake frosting! You’ll love this blackberry lemon cake with blackberry filling and lemon curd!
Preheat oven to 350°F. Line the bottoms of three 8-inch cake pans with parchment paper and spray with baking spray.
In a large bowl or the bowl of a stand mixer, press zest into sugar to release oils.
zest of two lemons, 1½ cup granulated sugar
Add softened butter and cream 3-5 minutes or until fluffy.
1½ cup granulated sugar, ½ cup salted butter
Add eggs, one at a time, followed by oil and vanilla extract, mixing until incorporated after each addition.
3 large eggs, ¼ cup vegetable oil, 2 teaspoon pure vanilla extract
In a separate bowl, whisk together flour, baking powder, and baking soda.
2½ cup cake flour, 1½ teaspoon baking powder, ½ teaspoon baking soda
Gently stir in blackberries to coat with flour mixture. Set aside.
1 cup blackberries
In another bowl, whisk together sour cream and lemon juice until smooth.
1 cup sour cream, ⅓ cup fresh lemon juice
Add ⅓ of flour-blackberry mixture to batter and mix just until incorporated, then follow with ½ of sour cream mixture. Repeat; then finish with final third of flour mixture, mixing just until combined.
Spoon batter evenly into three prepared baking pans and drop onto the counter from an inch or two of height to minimize air bubbles.
Bake in preheated oven for 25 minutes or until a toothpick entered into the center comes out clean.
Prepare Blackberry Buttercream
Purée blackberries with a blender or food processor and push purée through a fine-mesh sieve to strain out seeds.
1 cup blackberries
Add purée and lemon juice to a small saucepan and simmer over medium heat 5-10 minutes until reduced.
¼ cup fresh lemon juice
Measure out ⅓ cup of puree and add to a large bowl with softened butter. Beat with an electric mixer until creamy and well combined.
1 ½ cup salted butter
Add vanilla and mix well. Gradually mix in powdered sugar on low speed, then increase speed to whip for 2-4 minutes or until buttercream is light and fluffy.
2 teaspoon pure vanilla extract, 6 cup powdered sugar
Assemble Cake
Place one cooled cake layer on a cake board or cake stand.
Spread a thin layer of blackberry buttercream over cake layer and use a piping bag to pipe a buttercream border around its edge.
Add about ⅓ cup of lemon curd inside piped border and smooth to fill.
1 cup lemon curd
Top with second cake layer and repeat steps 2 and 3.
Top with final cake layer and continue to frost cake as desired.
Video
Notes
Blackberries: Feel free to use frozen blackberries in either the cake layers or the blackberry buttercream frosting. Just be sure to thaw and drain the blackberries before adding to the recipe.Lemon Curd: You can use either store-bought lemon curd, or make your own at home! Check out my Lemon Curd Cookies recipe for my recipe for homemade lemon curd! Prepare your lemon curd a few hours or a day in advance to allow it to set fully before assembling your lemon and blackberry cake!Cake Flour Substitute: If you don’t have cake flour, you can make a substitute to use in this lemon and blackberry cake recipe! All you need is all-purpose flour and corn starch. Just measure out 2 ½ cups of all-purpose flour and replace 5 tablespoons of it with cornstarch. In grams, it’ll be 312 grams of all-purpose flour sifted with 40 grams of cornstarch. As I mentioned above, it’s best to measure by weight with a kitchen scale, but if you don’t have one be sure to use the spoon-and-level method to measure by volume.Sour Cream Alternatives: If you don't have full-fat sour cream, you can use greek yogurt, or a low-fat sour cream as an alternative.