This Sourdough Discard Carrot Cake is incredibly moist and packed with flavor, and the sour cream frosting gives it just the right amount of tang. It's perfect for spring baking (and a great Easter dessert!), but honestly, I would eat carrot cake any time!

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Why you'll love this recipe
- This Sourdough Discard Carrot Cake is easy to make and packed with flavor!
- The sour cream frosting can also be made with cream cheese (instead of sour cream), and is a wonderful, tangy complement to the sweetness of the cake.
- This cake is very moist and will stay nicely moist for several days, making it easy to enjoy leftovers in the days after baking!
- Sourdough Discard Carrot Cake is a great way to use up some of your sourdough discard while making a tasty Easter dessert!
- This cake isn't overly sweet and would be delicious for a brunch. You might also like these Sourdough Discard Scones and this Sourdough Lemon Raspberry Loaf Cake!
Ingredients
There are a handful of ingredients you'll need to bring this Sourdough Discard Carrot 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 that uses 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.
- Shredded carrots: Shred the carrots on the small holes of a box grater. Shredding on the large holes will work, but using the small shred will help the carrots disperse more evenly throughout the cake. Using a microplane to shred the carrots is not necessary, but if you want the carrots to "melt in" to the cake more, this works well!
- Walnuts & raisins: These are optional, but I highly recommend adding walnuts and raisins to the cake batter!
- Sour cream: I used Violife Just Like Sour Cream, a dairy-free sour cream, which worked well. This recipe would work just as well with regular dairy sour cream, or cream cheese.
- If you are making the frosting with cream cheese, a quick note that I did try this with Violife Just Like Cream Cheese and it did not produce the flavor or texture that I was looking for. If you're looking for a dairy-free frosting option, I'd go the sour cream route!
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.
- Add shredded coconut - Add ½ cup shredded coconut to the batter as you're folding in the carrots, walnuts and raisins.
- Walnuts and raisins are optional, but highly recommended! You could also easily switch this out for a different nut and dried fruit combination!
- Make a cream cheese frosting - The recipe uses a sour cream frosting, but you can easily substitute the sour cream for cream cheese to make a cream cheese frosting instead. It would be a 1:1 substitution (sour cream to cream cheese).
- If you're interested in other spring baking recipes, try this Sourdough Discard Strawberry Cake and these Sourdough Discard Blueberry Bagels.
I have not tested this recipe with other variations, but if you do, let us know how it turns out in the comments! I always love to hear how you're adapting these recipes and use those as ideas for future recipes as well!
How to Make Sourdough Discard Carrot Cake
The key to this recipe is not overmixing the batter when you're combining the wet and dry ingredients. The full recipe with detailed instructions is at the bottom of this post.
- Step 1: Whisk together the dry ingredients (minus the sugars).
- Step 2: Shred your carrots on the small holes of a box grater.
- Step 3: Blend together the wet ingredients, plus sugars.
- Step 4: Fold the dry ingredients into the wet ingredients, stirring just until no dry spots remain.
- Step 5: Fold in the carrots, raisins, and chopped nuts.
- Step 6: Pour the cake into the prepared baking pan.
- Step 7: Once the cake has cooled, whip together the ingredients for the frosting.
- Step 8: Spread the frosting on the cake, slice, and serve.
Expert Baking Tips
- Shred the carrots using the small holes on a box grater. Using the large holes will work, too, but a smaller shred helps the carrots disperse more evenly in the cake batter rather than sinking.
- The walnuts and raisins are optional, but I highly recommend them! The texture of a carrot cake (including these add-ins) is part of the fun! If you like them, I also recommend these Sourdough Discard Cinnamon Raisin Bagels!
- Don't overmix the batter. When you're adding the dry ingredients into the wet ingredients, and then folding in the carrots, etc., make sure to mix until just combined.
- When baking, try to resist opening the oven! Let the cake bake for the full time. Carrot cake is much darker than most regular cake batters, so it's tempting to think that it's "done" much earlier than it really is if you're judging by color alone.
- Let the cake cool fully before frosting. If the cake is still warm, the frosting will melt.
- If you're looking for other snacking cakes, try this Sourdough Lemon Loaf Cake.
Shredding the Carrots
Shred the carrots on a box grater using the smaller holes. You can use the big holes, but a smaller shred will allow the carrots to disperse more evenly throughout the cake batter (larger shreds tend to sink in the batter).
Using a microplane to shred the carrots is unnecessary, although it does work. With such a fine shred, these carrots will "melt" into the cake more and will be less visible after baking.
Storage
Room Temperature Storage: Store this Sourdough Discard Carrot Cake covered at room temperature for up to 3 days. Keep in mind that the "cut" side of the cake will dry out first. You can place a piece of plastic wrap on that side of the cake to try to prevent that drying.
Freezer Storage: You can freeze the entire cake either before or after frosting.
- To freeze before frosting: Let the cake cool fully, then wrap the cake in plastic wrap, followed by aluminum foil (or a freezer-safe bag). Freeze for up to 3 months. You will frost the cake after thawing when you are ready to serve.
- To freeze after frosting: Freeze the full, frosted cake on a plate or baking sheet for about 60 minutes to set the frosting. Then, cut the cake into pieces (as you like, or leave the cake whole) and wrap the cake in plastic wrap, then aluminum foil (or a freezer-safe bag). Freeze for up to 3 months.
- Thawing frozen cake: When ready to serve, let the cake thaw in the fridge overnight or at room temperature for a few hours. Then, slice and serve.
Recipe FAQ
Sourdough discard is what is leftover after you feed your sourdough starter. You can either literally discard it (in the trash or compost), or you can use it to make sourdough discard recipes like this one!
If you're new to working with sourdough starter, check out these in-depth posts on how to feed sourdough starter, how to use sourdough discard, and tips for struggling sourdough starter.
Yes, this should work, but I'll be honest that I have not tested it! If you do, keep an eye on the baking time as cupcakes may not need as long as the full cake in order to be baked through fully.
If you don't have a 9x9-inch baking pan, you might be considering a 9-inch round pan. Let's get mathy for a minute: a 9x9-inch square pan has an area of 81 square inches. A 9-inch round pan has an area of approximately 64 square inches. So a 9-inch round pan is about 21% smaller than a 9x9-inch square pan (which this recipe was designed for).
That said, you could try to bake this in a 9-inch round, but I'd recommend covering with aluminum foil toward the end of the baking time. You'll also likely need to add some additional time for the cake to bake through fully. Another option would be to reduce each of the ingredients by about 20% to make the recipe proportional for a 9-inch round pan (easier said than done, I realize!).
Yes! You can use the same directions for the frosting, but replace the sour cream with cream cheese in order to make this a cream cheese frosting.
If you are making the frosting with cream cheese, a quick note that I did try this with Violife Just Like Cream Cheese, and it did not produce the flavor or texture that I was looking for. If you're looking for a dairy-free frosting option, I'd go the sour cream route!
No! I use dairy-free sour cream because I am lactose intolerant, and that works well for me. The frosting will work just as well with regular dairy sour cream (or cream cheese, if you're making that substitution).
Sourdough Discard Carrot Cake
Ingredients
For the Cake:
- ¾ cup all-purpose flour
- 1 ½ teaspoons baking soda
- 1 ½ teaspoons baking powder
- 1 ½ teaspoons ground cinnamon
- 1 teaspoon ground ginger
- ½ teaspoon ground cloves
- ½ teaspoon ground nutmeg
- ¼ teaspoon kosher salt
- ⅔ cup brown sugar packed
- ⅔ cup granulated sugar
- ⅓ cup vegetable oil
- 2 eggs
- 1 ½ teaspoons vanilla extract
- 200 grams (about ¾ cup) sourdough discard unfed, at room temperature
- 2 cups shredded carrots
- ½ cup chopped walnuts optional
- ¼ cup raisins optional
For the Frosting:
- 4 Tablespoons unsalted butter softened
- 4 Tablepsoons non-dairy or regular dairy sour cream at room temperature
- ½ teaspoon vanilla extract
- 1 ¾ cups confectioner's sugar
Instructions
- Preheat the oven to 350℉. Grease and flour a 9x9-inch baking pan*, then set aside.
- In a small bowl, whisk together the flour, baking soda, baking powder, cinnamon, ginger, cloves, nutmeg, and salt. Set aside.
- Peel and shred your carrots using the small holes of a box grater. Set aside.
- In a large bowl, use a hand-held mixer to mix together the sugars, oil, eggs, and vanilla extract until smooth and fluffy, about 1 minute. Add the sourdough discard and mix until smooth. Fold the dry ingredients into the wet ingredients and mix until just combined and no dry spots remain. Fold in the carrots, nuts and raisins and mix until just combined. Transfer your batter to the prepared baking pan.
- Bake for 45-50 minutes or until a toothpick inserted in the center of the cake comes out clean. Let the cake cool in the pan for about 15 minutes, then transfer to a cooling rack to cool fully.
- After the cake has cooled, make the frosting. In a medium bowl, whip the butter with a hand-held mixer until smooth and creamy, about 2-3 minutes. Add the sour cream and vanilla extract, and mix until smooth. Add the powdered sugar and mix until smooth. If the icing seems too thick, add more sour cream (1 Tablespoon at a time) to reach a thinner consistency.
- Transfer the cooled cake to a serving plate or board, then spread the cake with the frosting. Slice and serve!
Keely says
Probably the best carrot cake I've ever had! Moist, and deeeelicious!! I swapped out the vegetable oil for canola as it was all I had and everything else I followed to the T. My family not requests this delicious desert but I think I will do a cream cheese frosting next time. Overall, great recipe!!
Jessica Vogl says
I loveeee to hear that! And noted on the cream cheese frosting! I really appreciate your feedback.
Jessica Vogl says
Loved making this cake and sharing it with our neighbors! Two thumbs up from everyone!