Light, sweet, and buttery, this sourdough vanilla cake is a great way to use up extra sourdough discard. Topped with homemade buttercream frosting, this makes the best birthday cake.

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I never really need an excuse to make cake, but we have plenty of birthdays to celebrate around these parts. I’ve made my chocolate version many, many times, but I thought a vanilla sourdough cake would be a lovely and lighter version.
This recipe is a great one to keep in your back pocket. Whether you need it for a special holiday or a Tuesday, this is the perfect way to use up all that sourdough discard you may have from feeding your sourdough.
Although, at this point, I never toss out my discard. I just continue to feed and use it. There are so many great ways to use discard. Check out my favorite discard recipes here.
This light, fluffy, and moist cake is then topped with homemade buttercream frosting (recipe below) for the yummiest sweet treat.

Sourdough Cake Making Tips:
- Make sure to allow the cake to completely cool before frosting. If you don’t, you will be left with melted frosting.
- To ensure the cake doesn’t stick to the pan, I like to grease the pan first, then cut out a piece of parchment paper to fit in the bottom of the greased pan. When the cake is done baking, you just need to use a knife around the edges of the cake to loosen it from the sides and pop it out.
- Make sure the baking powder and baking soda are still good. If they are past their prime, then the cake won’t rise properly.
- This recipe can be doubled to make extra layers.
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Why you will love this recipe:
Delicious and sweet cake that is light and fluffy with vanilla and buttery notes.
Tender crumb.
Can be long fermented for the best digestibility and health benefits… if cake can really be healthy.
Great way to use discard.
Just mix it up and bake right away or it can be long fermented.
FAQ

What does sourdough do for cakes?
It helps reduce the gluten formation in the cakes which helps it be more tender rather than tough and chewy. It can also give cake a wonderful, mild sourdough flavor adding more depth.
Is sourdough hard to bake?
This is completely dependent on the recipe. There is such a wide variety of sourdough recipes and ways to use your sourdough starter. Some are super easy, like pancakes, while others are more complex, like artisan bread.
What kind of sourdough starter works for this recipe?
Active or discard will work. Also, I use a starter with 100% hydration. I feed it equal parts flour to water. If your starter is a different hydration, then it will affect the outcome of the cake.

Sourdough Cake Ingredients:
- Flour – This recipe calls for all-purpose.
- Sugar – Preferably cane sugar as many white sugars on the market are made from genetically modified sugar beets.
- Salt – Salt brings out the sweetness and adds so much flavor to desserts.
- Baking soda and baking powder – While this recipe is technically sourdough, the starter is not what gives its rise. This recipe still relies on chemical leaveners.
- Butter and coconut oil – This gives it a nice subtle flavor and lightness.
- Vanilla extract – Preferably pure vanilla extract, but imitation would also work. I love making my own homemade vanilla extract. It is really easy and inexpensive to make.
- Sourdough starter – This can be active sourdough starter or discard. Either will work.
- Water or milk – I typically use milk. If you want to long-ferment the cake and don’t feel comfortable leaving the milk out, substitute it for water.
- Eggs
Tools you may need:
Liquid measuring cup
Dry measuring cups and spoons
9×13 baking dish or cake pan

How To Make Sourdough Vanilla Cake
Preheat the oven to 350 and grease a 9×13 baking dish or two 9” cake pans.
Tip: if using cake pans, I like to grease the cake pans and then cut out parchment paper the size of the cake pan and add it to the bottom. This is extra security that it will not stick to the bottom.

In a stand mixer bowl or large bowl, combine the dry ingredients.

Add the softened butter to the flour mixture and combine.
In a separate bowl, mix together sourdough starter, milk, eggs, melted coconut oil and vanilla.
Slowly add the wet ingredients to the butter flour mixture. Start the mixer on low and work up to medium speed.
Mix until smooth without lumps.

Add the fermented sourdough cake batter to the baking dish or half the batter to each cake pan.
Bake for 30-35 minutes until it starts to turn golden around the edges and a cake tester comes out clean.
Allow to cool completely before frosting.

How To Make Long Fermented Sourdough Cake
In a large bowl, mix together oil, butter, flour, sourdough starter, and water until combined.
Cover with a tea towel or plastic wrap and allow to ferment in a warm place for 8-24 hours.
The next day, preheat the oven to 350 and grease a 9×13″ baking dish or two 9” cake pans.
Add vanilla, eggs, salt, sugar, baking soda and baking powder to the fermented dough. Stir until it just comes together and is combined well, but being careful not to over mix the batter.
Add half of the fermented sourdough cake batter to each cake pan.
Bake for 30-35 minutes for a 9×13 or until a cake tester comes out clean. 35-45 minutes for 9″ can pans.
Allow to cool completely before frosting.
Make them into cupcakes:
Mix according to the instructions and place in paper lined muffin tin. Bake for 18-22 minutes or until a toothpick comes out clean.
Storage:
Frosted cake: Place in the refrigerator for about 15-20 minutes uncovered, then cover with plastic wrap or beeswax wrap. This lets the frosting harden before topping it so hopefully the frosting stays nice. Allow it to thaw at room temperature for at least 20-30 minutes before serving.
Unfrosted: Store at room temperature in an airtight container.

How To Make The Best Buttercream Frosting:
To a stand mixer with a whisk attachment (or a bowl and hand mixer), add softened butter and beat until smooth.
Add powdered sugar and start the mixer on low and work up to medium speed. Whisk until nice and fluffy. Scrape the sides of the bowl as needed.
Add heavy whipping cream, salt, and vanilla and whisk for 1-2 more minutes.
Spread onto completely cooled cake.
If you make this recipe and love it, I would love if you gave it 5 stars! Tag me on Instagram @farmhouseonboone with your delicious creation.
Find More Sourdough Desserts
- Sourdough Coffee Cake
- Lemon Pound Cake
- Blueberry Sourdough Cobbler
- Sourdough Biscotti
- Sourdough Brownies
Sourdough Vanilla Cake

Ingredients
- 2 1/2 cups flour
- 2 cups sugar
- 1 teaspoon salt
- 1 teaspoon baking soda
- 2 teaspoons baking powder
- 1/4 cup butter, softened
- 1/4 cup coconut oil
- 1 1/2 tablespoons vanilla
- 1/2 cup sourdough starter
- 1 cups water/milk
- 3 large eggs
Buttercream Frosting
- 1 cup unsalted butter, room temperature
- 4 cups powdered sugar
- 1/4 cup heavy cream
- 1 tablespoon vanilla extract
- 1/2 teaspoon salt
Instructions
- Preheat the oven to 350 and grease a 9×13 baking dish or two 9” cake pans.
- In a stand mixer bowl or large bowl, combine the dry ingredients.
- Add the softened butter to the flour mixture and combine.
- In a separate bowl, mix together sourdough starter, milk, eggs, melted coconut oil and vanilla.
- Slowly add the wet ingredients to the butter flour mixture. Start the mixer on low and work up to medium speed.
- Mix until smooth without lumps.
- Bake for 30-35 minutes until it starts to turn golden around the edges and a cake tester comes out clean. 35-45 minutes for 9" cake pans
- Allow to cool completely before frosting.
Create Buttercream Frosting
- To a stand mixer with a whisk attachment (or a bowl and hand mixer), add softened butter and beat until smooth.
- Add powdered sugar and start the mixer on low and work up to medium speed. Whisk until nice and fluffy. Scrape the sides of the bowl as needed.
- Add whipping cream, salt, and vanilla and whisk for 1-2 more minutes.
- Spread onto completely cooled cake.
Notes
- If using cake pans, ensure the cake doesn’t stick to the pan by greasing the pan first, then cutting out a piece of parchment paper to fit in the bottom of the greased pan. When the cake is done baking, you just need to use a knife around the edges of the cake to loosen it from the sides and pop it out.
- Make sure the baking powder and baking soda are still good. If they are past their prime, then the cake won’t rise properly.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.


















Can I make this & freeze it? With or without the frosting? Any tips on if/how to freeze it is much appreciated! Excited to make this for my little boy’s birthday!
I would freeze it without the frosting on it it! Freeze it in a safe baking dish that won’t crack in the freezer!
Do you have any recommendations for baking on a sheet tray. I want to cut out mini cakes.
Can I substitute maple syrup for the sugar? Do you know how much if so? I making a smash cake for my one year old today 😃
Yes, the same amount!
I made this today and it as incredible!
Hi Lisa! Does it taste pretty coconut-y because of the coconut oil? Would it be ok to substitute avocado oil instead?
I don’t taste it! You can use avocado oil though.
Ok thanks!
This was AMAZING! Thank you Lisa! I made it last week for our sons 7th bday and our older 2 kids have bdays in Dec and requested the same cake. I love how moist the crumb is. Keep up the good work! God bless you!
Not only did my mom love her birthday cake my so wants it for his cake. LOL
Hi, can you use raw milk for the long ferment?
Thanks x
Yes, that’s fine.
This will be the 3rd time using your cake recipe with fermenting it. I have bit of a stiffer sourdough starter so when I mix it to long ferment it looks like other bread doughs I’ve done. Is that how it’s supposed to look like? I also like to use all butter in this cake. I’ve made it for our girls’ birthday, but the last one turned out kinda flat and bubbly looking. Hopefully this time it doesn’t turn out like that and I won’t ferment it very long today. So maybe that’s what happened it went for too long or I over mixed. I’m also using a mixer instead of hand mixing.
My family loved this cake! I would suggest not adding the melted coconut oil until you are adding in the wet ingredients. My coconut oil turned back to solid quickly. I could not get it blended in well. Next time I make this I will try it in the 9” rounds to see if it bakes more evenly. The frosting makes plenty! If I bake another cake in a 9×13 pan I will make a half batch of frosting.
Same. My coconut oil does not work well in cakes. I don’t use it anymore.