This Sourdough Vanilla Sheet Cake is the perfect cake for any celebration: birthdays, 4th of July, graduation, and more! It's light and fluffy and topped with a vanilla buttercream frosting (and sprinkles to suit any occasion). And it comes together with less than 30 minutes of hands-on time, so it's an easy recipe to make for a crowd.
Why you'll love this recipe
- This Sourdough Vanilla Sheet Cake is light and fluffy, and topped with a vanilla buttercream frosting. And it stays soft and moist for days after baking!
- It's an easy recipe that comes together with less than 30 minutes of hands-on time.
- Looking for other easy cake recipes? Try this Sourdough Lemon Blueberry Cake and this Sourdough Discard Strawberry Cake.
- You can easily customize this recipe for any occasion with food coloring (for the icing) and sprinkles!
- This recipe is made with sourdough discard, but you can easily modify to use active sourdough starter if you prefer.
- Sheet cake is served directly from the baking pan, so you can bake, let it cool completely in the pan, frost, and serve! As simple as it gets!
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Ingredients
There are only a few key ingredients you'll need to bring this vanilla sheet cake together.
- Sourdough discard: The sourdough discard should be unfed and at room temperature for this recipe. This recipe is designed for a sourdough starter with a 1:1 ratio (when you feed your starter, it's with 1 part flour and 1 part water). If your starter uses a different ratio, you may need to adjust some of the ingredients in this recipe.
- Learn more about how to make a sourdough starter.
- Butter: The butter must be softened to room temperature for this recipe (both for the cake batter and the buttercream frosting). I often will leave butter out on the counter overnight if I know I want softened butter the next day!
- Sprinkles: These are optional, but also a great way to customize this cake! Choose your favorite sprinkles to make this cake for any occasion.
- In the mood for sprinkles? Try these Sourdough Discard Sugar Cookie Bars and these Sourdough Lofthouse Cookies, too.
See full recipe below for detailed directions.
Substitutions & Variations
This is a very adaptable recipe and below are a few easy substitutions and variations you can try.
- Use active sourdough starter - If you'd like to make this recipe with active sourdough starter, you can! To do so, omit the yeast and replace the sourdough discard with active starter (200g). You will also need to increase the rise times.
- Sour cream substitute - This recipe uses sour cream for moisture and fat content. If you don't have any on hand, you can easily substitute with Greek yogurt (preferable) or regular yogurt.
- Add color to your frosting - This recipe makes a vanilla buttercream frosting, but add a few drops of food coloring if you'd like to make a colorful cake! Sprinkles are also a great way to customize your cake for any event.
How to Make Sourdough Vanilla Sheet Cake
There are only a few key steps to bring this recipe together. The full recipe with detailed directions is at the bottom of this post.
- Step 1: Mix together the dry ingredients (minus the sugar).
- Step 2: Cream together the butter and sugar. Mix in the remaining wet ingredients.
- Step 3: Add the dry ingredients to the wet ingredients. Mix until smooth and combined. Pour into a 9x13-inch baking pan.
- Step 4: Bake until the cake is set and lightly browned. A toothpick inserted in the center should come out clean. Let the cake cool fully before frosting.
- Step 5: Mix together the buttercream frosting.
- Step 6: Spread the frosting on the cooled cake, then add sprinkles. Slice and serve directly from the baking pan.
Expert Baking Tips
- Use metric measurements for at least the flour and sourdough discard. These are two ingredients where there can be a huge variation in using cups vs. metric measurements. Using a kitchen scale for metric measurements for at least these two ingredients will set you on the right path!
- Make sure your butter is room temperature so that it creams together properly (for the cake batter and the buttercream frosting).
- Let the cake cool completely before frosting so the frosting doesn't melt.
- Customize this cake with different frosting colors and sprinkles.
- Serve this sheet cake straight from the pan! It makes it easy to take to any gathering!
Storage
Room Temperature Storage: Store this cake covered or in an airtight container at room for 1-2 days.
Refrigerator Storage: Store this cake covered or in an airtight container in the refrigerator for up to 3-5 days. Refrigeration is not necessary, but will preserve the cake for longer.
Freezer Storage: You can also freeze this cake. Make sure it has cooled fully, then slice and transfer to a freezer-safe container and freeze for up to 3 months. You can also freeze the full cake in the baking pan, if you prefer. When you're ready to serve, thaw overnight in the refrigerator, then let it come to room temperature before serving.
Recipe FAQs
They're accurate! I use the metric measurements for my own baking, especially with the flour and sourdough discard, so I recommend you do the same! There can be such a huge variation in cups measurements, particularly for those two ingredients.
Yes, absolutely! Add a few drops of food coloring to make any frosting color you like. Sprinkles are also a great way to customize your cake for any occasion!
You can serve this cake straight from the baking pan. If you prefer, you can also flip the cake onto a platter or cutting board, add the frosting, and serve from the platter.
More Sourdough Cake Recipes
If you tried this Sourdough Vanilla Sheet Cake or any other recipe on my website, please leave a ⭐ star rating and let me know how it went in the comments below. I'd love to hear from you! Happy Baking!
Sourdough Vanilla Sheet Cake
Ingredients
For the Cake
- 1 ¼ cups all-purpose flour
- 2 Tablespoons cornstarch
- 1 ½ teaspoons baking powder
- ½ teaspoon baking soda
- ½ teaspoon kosher salt
- ¾ cup unsalted butter softened
- 1 ½ cups granulated sugar
- 200 grams (about ¾ cup) sourdough discard unfed, at room temperature
- 3 eggs room temperature
- ⅓ cup sour cream non-dairy or regular dairy
- ¼ cup milk room temperature, non-dairy or regular dairy
- 2 teaspoons vanilla extract
For the Buttercream Frosting
- 1 cup unsalted butter softened
- 3 ½ cups confectioner's sugar
- 2 Tablespoons milk non-dairy or regular dairy
- 2 teaspoons vanilla extract
- Sprinkles optional
Instructions
- Preheat oven to 325℉ (165℃). Spray a 9x13-inch baking pan with cooking spray, then line with parchment paper to cover the bottom of the pan. Spray the top of the parchment paper with cooking spray again. Set aside.
- In a medium-sized bowl, whisk together the flour, cornstarch, baking powder, baking soda, and salt. Set aside.
- In a large bowl, use a hand-held mixer to cream together the butter and the sugar until light and fluffy, about 2-3 minutes. Add the sourdough discard, eggs, sour cream, milk, and vanilla. Mix until smooth and combined.
- Add the dry ingredients into the wet ingredients and mix until smooth and combined. Pour the cake batter into the prepared baking pan. If needed, jiggle the pan to distribute the batter evenly.
- Bake for 30-35 minutes or until the cake is set and lightly browned at the edges. A toothpick inserted in the center of the cake should come out clean. Set the cake in the baking pan on a wire rack to cool fully (at least an hour) before frosting.
- To make the frosting, use a hand-held mixer to cream the butter in a medium-sized bowl until light and smooth, 2-3 minutes. Slowly mix in the confectioner's sugar. Add the milk and vanilla extract and mix until fully smooth and incorporated. Add more milk if you feel that the frosting in too thick.
- Spread the cooled cake with a layer of frosting, then top with sprinkles (optional). Slice and serve the cake directly from the baking pan.
Jessica Vogl says
A fan-favorite and perfect for any event! Will defintely be making this on repeat this summer!