This Lemon Blackberry Cake with lavender French buttercream is the perfect cake for summer! Every bite of this lavender cake is filled with incredible flavor, reminiscent of a summery, sunny French countryside.

Lemon blackberry cake with lavender French buttercream frosting

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You’ll love the not-too-sweet cake and cream combined with the zesty lemon and fruity blackberry. The lemon blackberry cake layers are delicate, very moist and bursting with lemon flavor. I love how the lemon zest complements the blackberry flavor.

Lavender Lemon Blackberry Cake Recipe

I am so excited to have Tatyana, one of my blogging friends, share her recipe for this gorgeous lavender cake from her new cookbook! She is such a talented baker and cook. I know you will love this recipe.

Can I Substitute Frozen Blackberries?

I recommend using fresh blackberries for this recipe for best results. If you don’t have fresh berries, frozen ones will work in a pinch.

blackberry cake slice

How to Make the Lemon Blackberry Cake Layers:

  • Make sure all the wet ingredients are at room temperature, that includes the eggs, butter and milk. I recommend warming the milk in the microwave for a minute so it’s warm.
  • Cream together the softened butter and sugar for a few minutes, until it’s light and fluffy.
  • Add the milk to the batter but don’t mix it in just yet. Add the dry ingredients, then use your stand mixer to mix everything together. And don’t overmix the batter, which will cause the cake layers to dome. Mix just until the dry ingredients are combined, about 1 minute.
  • To make the cake layers very light and delicate, I use a combination of all-purpose flour with almond flour. Sift that flour! This is so important; no one wants flour clumps in a cake slice.
  • Whisk the egg whites separately, then fold them into the batter last, adding even more volume to the batter.
How to make blackberry cake

What is French Buttercream?

I fell in love with French buttercream when I was writing my cookbook. There’s something so special about this buttercream that sets it apart from every other frosting recipe I’ve tried! It’s super silky, very smooth and not too sweet.

French Buttercream is made with egg yolks, butter and sugar syrup, which cooks the egg yolks so no need to worry about raw eggs. It’s easy to add flavor, too! You can make it with chocolate, caramel, fruit and extracts, like this recipe with lavender oil. If you’ve never tried it, you’re in for a treat!

How to Make French Buttercream Frosting:

  1. The sugar syrup: combine the water and sugar in an extra-small saucepan, attach a candy thermometer and resist the urge to stir! Stirring will cause sugar crystals to form on the sides of the pan; not good!
  2. The egg yolks: these need to be whisked for a few minutes before pouring in the sugar syrup. Then just let the magic happen! The extremely hot syrup will cook the yolks, turning them thick, pale and glossy.
  3. The butter: soften the butter slightly before adding it to the egg yolks. The butter needs to be added slowly, a few tablespoons at a time. As you’re adding the butter, the frosting will look a little funny. Don’t worry, everything will correct itself; you did not mess up! Just keep adding the butter and the frosting will come together!

Make sure to use lavender oil that is safe for consumption. Most oils are not, so make sure to check the label.

how to make French buttercream frosting

Want to learn more about French buttercream and how to make it? Check out my step-by-step video tutorial for Chocolate French Buttercream!

More Frosting Recipes to Try:

french buttercream frosting on blackberry cake
lavender lemon cake
4.67 from 30 votes

Lavender Lemon Blackberry Cake

Prep Time: 1 hour 45 minutes
Cook Time: 25 minutes
Total Time: 2 hours 10 minutes
This Lemon Blackberry Cake with lavender French buttercream is the perfect cake for summer! Every bite of this lavender cake is filled with incredible flavor. You’ll love the not-too-sweet cake and cream combined with the zesty lemon and fruity blackberry.

Ingredients 

Servings: 14

For Lemon Blackberry Cake Layers

For French Buttercream

Instructions

How to Make Lavender Cake:

  • Preheat oven to 350F (177C). Line three, 8-inch (20 cm) cake rounds with parchment paper and grease the sides.
  • In a large mixing bowl, cream together the butter and sugar with a hand mixer for 2 to 3 minutes, until light fluffy. Add the egg yolks, vanilla extract and lemon zest. Mix again until cream and smooth, then pour in the milk but do not mix.
  • In a separate bowl, combine all the dry ingredients: flour, almond flour, baking powder and salt. Sift the dry ingredients into the cake batter. Use a whisk or hand mixer to combine the dry ingredients, milk and batter, mixing just until the flour is incorporated.
  • In a separate bowl, whisk the egg whites high speed for 2 to 3 minutes, until medium peaks form. Add the egg whites to the cake batter and fold in using a spatula, folding gently but thoroughly until well combined.
  • Divide the cake batter evenly between the three cake pans, using a kitchen scale for accuracy. Toss the fresh blackberries in the cornstarch, coating the berries well. Drop 6 to 8 berries into each pan, spacing them equally apart. Bake the cakes in preheated oven for 25 minutes, or until a toothpick inserted into the center comes out clean. Remove from oven and cool completely on a wire rack.

How to Make French Buttercream Frosting:

  • While the cake layers are cooling, prepare the French buttercream. Place the egg yolks into a stand mixer bowl and whisk on high speed for 2 to 3 minutes, until thick and pale. 
  • Meanwhile, combine the water and sugar in a small saucepan. Stir once to combine the ingredients and attach a candy thermometer to the side. Cook the syrup over medium heat until it reaches 238F (114C), about 7 to 8 minutes. 
  • Once syrup is ready, remove from heat and with mixer on medium speed, pour the hot syrup into the egg yolks. Take care to pour the syrup away from the whisk attachment to prevent crystalized sugar bits. Once all the syrup is added, turn mixer up to high speed and whisk until the egg yolks are doubled in size and reaches medium peak stage; it should be cooled and just lukewarm to touch.
  • Begin adding the butter, about 1 tablespoon (15 g) at a time, mixing well after each addition. Add the butter slowly to prevent the cream from separating; this process takes about 8 to 10 minutes. As more butter is added, the cream will thicken and hold its shape. Add the lavender oil and purple food color last. 

Assembling the Lavender Cake:

  • Once cake layers have cooled, spread a generous amount of buttercream between each layer. Smooth the frosting over the top and sides. Garnish the top as desired, with blackberries, lavender and greens. 

Nutrition Per Serving

571kcal Calories43g Carbs6g Protein42g Fat24g Saturated Fat220mg Cholesterol80mg Sodium236mg Potassium1g Fiber30g Sugar1325IU Vitamin A2.1mg Vitamin C127mg Calcium1.5mg Iron
Nutrition Facts
Lavender Lemon Blackberry Cake
Amount per Serving
Calories
571
% Daily Value*
Fat
 
42
g
65
%
Saturated Fat
 
24
g
150
%
Cholesterol
 
220
mg
73
%
Sodium
 
80
mg
3
%
Potassium
 
236
mg
7
%
Carbohydrates
 
43
g
14
%
Fiber
 
1
g
4
%
Sugar
 
30
g
33
%
Protein
 
6
g
12
%
Vitamin A
 
1325
IU
27
%
Vitamin C
 
2.1
mg
3
%
Calcium
 
127
mg
13
%
Iron
 
1.5
mg
8
%
* Percent Daily Values are based on a 2000 calorie diet.
Course: Dessert
Cuisine: French
Keyword: lavender cake
Skill Level: Dessert
Cost to Make: $$$

This stunning cake recipe is from my newly released cake cookbook, The European Cake Cookbook. It’s the first recipe in the ‘Western Cake Recipes’ chapter, featuring decadent French cake recipes. This French-inspired cake is one of my favorites from the book.

What’s your favorite summer cake recipe or filling? Blackberries are definitely one of my favorites!