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Keeping this sweet, simple, and delicious with this Swirled Blackberry Lavender Sheet Cake. Light and fluffy vanilla cake swirled with homemade blackberry lavender jam. Then generously frosted a sweet vanilla bean white chocolate buttercream. This cake is nothing short of delicious. Every bite is layered with fresh berries, hints of lavender, and sweet vanilla cake. The perfect berry-filled cake for any and all occasions.

Swirled Blackberry Lavender Sheet Cake |

Happiest Friday everyone. We’re celebrating sweet cake and I am so excited. I’ve been holding onto this for a couple of weeks. I’ve wanted to share this since the day I first made it, but peach recipes took top priority last week. Which is totally fine, because of course, they too are so delicious.

This week, however, we’re switching to berries, cake, and frosting and it’s going to be pretty darn great.

Swirled Blackberry Lavender Sheet Cake |

The Inspiration

I would love to say that the inspiration for this cake was Asher’s upcoming 13th birthday. BUT, that girl wants nothing to do with a non-chocolate cake. So, as much as I would love to be remaking this for her birthday on the 30th, I’m sure I’ll be making the standard chocolate cake.

The real inspiration was super simple, I wanted to bake a cake. I wanted it to be light and happy and pretty. I want to have fun photographing it, and I wanted it to be my most delicious vanilla cake yet.

Excitedly reporting that this cake checks all of the above boxes. Sometimes you just have to make what you really, really want to make.

Swirled Blackberry Lavender Sheet Cake |

The details – starting with the jam

If you guys have followed along for a while you may remember my blackberry layer cake. This cake is very, very similar flavor-wise, but it’s simplified down into a yummy sheet cake.

The jam is quick, but delicious…fresh blackberries, sweet honey, dried lavender, and a squeeze of lemon. Boil everything together until the jam thickens up and turns jammy.

Swirled Blackberry Lavender Sheet Cake |

This isn’t your traditional jam however, it will not be jelly-like. It’s more of a sweet, thick blackberry sauce. Make the jam first so that it has plenty of time to cool off.

Pairing lavender with blackberries is a favorite combo of mine. The flora hints from the lavender compliment the sweetness of the blackberries, and when mixed together in a jam…

It is so good!

Swirled Blackberry Lavender Sheet Cake |

Onto the vanilla cake

When it comes to vanilla cake I like to keep my cake recipes pretty straightforward. And I always go heavy on the vanilla. I love to use real vanilla beans for added flavor, but of course, good olè vanilla extract works great too.

Mix the coconut oil with sour cream, eggs, sugar, and that vanilla. Then just add flour, baking powder, baking soda, and a nice pinch of salt. Stream in a little milk and that’s it. Simple. Simple.

Now pour the batter into a rectangle baker.

Swirled Blackberry Lavender Sheet Cake |

Now the fun part – swirl in the jam

Take the blackberry jam from earlier and dollop spoonfuls over the cake batter, then use a knife to gently swirl the jam around. Don’t over mix, the idea is to have pretty swirls of jam throughout the cake.

If you over-swirl, the cake will still be great, but more of a purple color.

Swirled Blackberry Lavender Sheet Cake |

While the cake bakes, make the frosting

Butter, sugar, lots of vanilla, and melted white chocolate, that’s what you’ll need. Beat that all together and you’ll have one of my favorite cake frostings.

No one ever knows there’s white chocolate in the frosting. But it’s what makes this buttercream extra special and leaves everyone wanting more.

Swirled Blackberry Lavender Sheet Cake |

Finish this up

Once the cake has cooled, spread over a thin layer of the blackberry jam, then dollop over that frosting. The frosting is sweet and creamy, and everything together is DELICIOUS.

Once again, take the jam and add small spoonfuls to the top of the baked cake. Then use a knife to gently swirl the jam into the frosting. It turns the prettiest shade of purple and I love it.

Swirled Blackberry Lavender Sheet Cake |

Yes, what I love most about this sheet cake is how just pretty it turns out with minimal effort. The beauty of a sheet cake is that you don’t have to cut or layer anything. Just bake, frost, and enjoy!

This is the perfect cake to make on a rainy summer afternoon. Especially if you have one too many boxes of sweet berries!

Swirled Blackberry Lavender Sheet Cake |

Looking for other sweet cake recipes? Here are some favorites:

Swirled Berry Ice Cream Butter Cake

Swirled Blueberry Lemon Thyme Cake

Coffee and Fudge Ice Cream Cak

Lastly, if you make this Swirled Blackberry Lavender Sheet Cake, be sure to leave a comment and/or give this recipe a rating! Above all, I love to hear from you guys and always do my best to respond to each and every comment. And of course, if you do make this recipe, don’t forget to tag me on Instagram! Looking through the photos of recipes you all have made is my favorite!

Swirled Blackberry Lavender Sheet Cake

Prep Time 30 minutes
Cook Time 30 minutes
Total Time 1 hour
Servings: 12
Calories Per Serving: 781 kcal

Nutritional information is only an estimate. The accuracy of the nutritional information for any recipe on this site is not guaranteed.


Blackberry Lavender Jam

Blackberry Cake

Vanilla White Chocolate Frosting


  • 1. To make the jam. Add the blackberries, honey, lemon juice, and lavender to a medium-size pot set over high heat. Bring the mixture to a boil, once boiling use a potato masher or fork to break down and mash the berries. Continue to cook for 5-8 minutes or until the jam has reduced and thickened by 1/3. Remove from the heat and let cool. This should thicken as it cools. 
    2. Preheat oven to 350° F.  Line a 9×13 inch baking dish with parchment paper.
    3. In a large bowl, beat together the coconut oil, sour cream, eggs, sugar, and vanilla. Add the flour, baking soda, baking powder, and salt. Mix until just combined, then slowly beat in the milk until fully combined
     4. Pour the batter into the prepared pan. Take about 1/2 cup to 3/4 cup of the jam and dollop it by the tablespoon over the cake. Use a knife to lightly swirl the jam around, don't over mix it.
    5. Bake 30-35 minutes, until the top is just set and no longer wiggly in the center. Remove and let cool completely before frosting.
    6. To make the frosting. In a large bowl, beat together the butter and powdered sugar until light and fluffy. Add the melted white chocolate and vanilla, beat until combined.
    7. Spread a thin layer of jam over the cake, then frost the cake all over. Add small spoonfuls of the jam to the frosting and gently swirl the jam into the frosting. Slice, eat and enjoy!
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Swirled Blackberry Lavender Sheet Cake |

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    1. Hi Shellie,
      Sure, that will be fine for you to use! Let me know if you have any other questions, I hope this is delish! xx

  1. I am hoping to make this for my mother-in-law’s birthday tomorrow! Would it work to spread the mixture between 2 round cake pans and layer the frosting in the middle and top? Would I need to adjust anything?

    1. Hey Madison,
      Unfortunately, this cake isn’t going to work as a layer cake, the frosting is just too soft. I would keep it as a sheet cake:) Please let me know if you have any other questions! xT

  2. 5 stars
    Made this cake for a dinner party, and it was a hit! Can’t wait to make again with freshly picked blackberries this summer!

    1. Hey Taylor,
      Happy Wednesday!! ❄️ I appreciate you making this recipe and sharing your feedback, so glad to hear it turned out well for you! xT

    1. Hey MaryCate,
      I don’t strain mine, but you totally could if you wanted:) I hope you love this recipe, let me know how it turns out! xx

  3. 10/10!!! I have made this several times and even modified with a vegan coconut cream frosting!! Devine! I grow blackberries and raspberries every year and always end up with a freezer full so I mix the berries in the jam for a little summer in the middle of winter. So yum!

    1. Hey Ali,
      Wonderful!! I appreciate you making this recipe and your comment, so glad to hear it was enjoyed! Have a great weekend:)

  4. This cake is amazing! My husband has already requested it for his birthday in September. It’s perfect for a potluck or family gathering. Thank you for sharing!

    1. Hey Allison,
      Happy Monday!!☃️ Thanks a lot for making this recipe and sharing your review, I love to hear that it was a winner! xx

    1. Hey Teresa,
      Happy Sunday!!❄️ I love to hear that this recipe was enjoyed, thanks so much for trying it out and sharing your feedback! xx

  5. Good morning. I recently found your website and I’ve made a few recipes, all of which have been fantastic! So, thank you!
    This cake looks so good! I am going to make it today. I have all of the ingredients on hand, except for the sour cream. Would non fat Greek yogurt be an acceptable substitute or would you recommend a trip to the grocery store to pick up the sour cream? Thank 🙂

    1. Hey Lisa,
      Thanks so much for your kind message! Greek yogurt would be great to use! I hope you love the recipe, please let me know if you give it a try! xT

    1. Hey Sara,
      You could use another neutral oil in place of the coconut oil. Please let me know if you have any other questions! xT

  6. 5 stars
    I’m wanting to bring this to Friendsgiving this Saturday..Only problem is, our drive is almost 3 hours. Would that be possible and if so, what would be the best way to transport? Should I fully make the cake with icing and all and just let it ride in my backseat or should I put it in a large cooler? Any help would be so appreciated!

    1. Hey Carissa,
      As long as your car isn’t super hot, this will be just fine covered at room temp for your travels. I hope you love the recipe, please let me know if you give it a try! xT

  7. 5 stars
    I can not begin to tell you how amazing this cake was. I was so intimidated by it initially since it’s essentially a 3 part recipe but I’m so glad I made it. The jam was also a hit with everyone and there was enough leftover that I sent big spoonfuls home in Tupperware with left over cake.

    1. Hey Carissa,
      Wonderful! I love to hear that this recipe was enjoyed and appreciate you giving it a try! Have a great weekend!🍁

  8. I’m making this for guests tomorrow! Can I leave it covered on the counter for 24 hours or does it need to be refrigerated?

    1. Hi Shannon,
      Yes, you can keep in an airtight container and it will be just fine! I hope this recipe turns out amazing for you! xx

    1. Hi there,
      Sure, that should work well for you!! I hope you love this recipe, please let me know if you give it a try! xx

    1. Hey Channing,
      Sure, you could use a square pan and then you’ll have extra batter for cupcakes! I hope this recipe turns out amazing for you, please let me know if you have any other questions! xT

  9. Don’t have any white chocolate on hand! How would you recommend going about that? Just sub with a vanilla frosting recipe?

    1. Hi Pari,
      You can just skip the white chocolate. Please let me know if you give this recipe a try, I hope you love it! xx