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A moist and tender cake with swirls of buttery sweetness

This Sourdough Discard Carrot Cake with Brown Butter Cream Cheese Frosting boasts a moist and tender crumb that includes a generous measure of sourdough discard. The sweetness of fresh spring carrots is complemented with fresh orange zest along with warming cinnamon, nutmeg, and cloves, and an optional (but encouraged) measure of walnuts and raisins. Swirls of brown butter and vanilla bean-flecked cream cheese frosting adorn the top adding a buttery sweetness with just a hint of orange.

What is sourdough discard?

Sourdough discard is simply the portion of ripe sourdough you remove when feeding your starter. If like me, you also have a seemingly neverending supply of sourdough discard from your daily feedings, this carrot cake recipe is a perfect way to use some of it up -- in fact, it uses 270 g or about 1 cup of sourdough discard. Some of my other favorite sourdough discard recipes can be found here.

How to ensure a moist and flavorful carrot cake

Oil instead of butter - In general, cakes baked with oil such as canola oil or vegetable oil result in a moister, more tender bake with a more even crumb than using other fats such as butter. One reason is that oil remains liquid at room temperature, whereas butter will solidify, so you end up with a moister (feeling) cake. The other is that oil is pure fat so it will not encourage gluten formation to the same extent that butter (which is 80% fat / 20% water) does, leading to a cake that is more tender.
Apple sauce - My secret weapon for encouraging a moist crumb without sacrificing flavor is to use a measure of applesauce in addition to the oil. The one downside of oil (and one of the reasons some prefer to bake with butter) is that too much can ruin a cake by overwhelming the flavor with a distinct "oilyness." This is easily remedied for carrot cake by using part neutral oil like canola or vegetable oil and part applesauce which helps retain moisture and adds a nice sweetness that compliments the flavor of carrot cake well.
Sugar - Not only does sugar sweeten the flavor of the cake, it also helps the cake brown and caramelize, which adds to the flavor profile. In addition to flavoring the cake, it's also important for providing structure and ensuring a moist crumb because sugar molecules will cling to water helping to ensure moistness in the cake.
Freshly shredded carrots - Carrots are roughly 86-95% water on average so they greatly contribute to the moisture of carrot cake. However, I implore you not to buy pre-shredded carrots for this cake because they are often brittle and dry, disgorged of much of their excess liquid during production. Shred fresh carrots yourself for finer and more tender carrots that retain so much more of their liquid than pre-shredded.
Don't overbake it - Water starts to steam at 212 degrees F / 100 C so it's important that you pull your cake out of the oven before it reaches that temperature otherwise it is more likely to dry out. 200-210 degrees F / 93-99 C is the range you're aiming for to obtain a properly baked carrot cake.

How do I know when my carrot cake is fully baked?

Check for visual cues

For carrot cake, the top should be nicely golden. You'll also want to look at the edges of the cake as it will pull away from the edges once done.

Check the cake for springiness

Gently press the top and see if it springs back. If the cake is nice and squishy it's a good indicator that the cake is fully baked. If it's still jiggly or your fingertips leave dents, it's an easy indicator that it's not done yet.

Take the temperature

If your cake passes the spring test, it's a great idea to check the temperature with a probe thermometer next. For dense cakes like carrot cake, you're looking for an internal temperature between 200-210 degrees F / 93-99 C. This is the thermometer I use in my kitchen.

Why the toothpick test isn't a great test for carrot cake

One popular way to test a cake's doneness is to insert a toothpick or skewer into the cake and if it comes out with batter or crumbs it's recommended that you continue to bake further. However, because carrot cake is so moist and dense this is not a great indicator for checking its doneness. Though you definitely want to continue baking is you see liquid batter, a few crumbs on the toothpick or skewer are totally normal. If you continue baking until you see no crumbs, you're likely to overbake the carrot cake.

Does this sourdough discard carrot cake have nuts or raisins?

Yes, I love to use both walnuts and raisins in this cake. But they are both totally optional! This cake is super delicious either way.

Love nuts, but not walnuts? Pecans make a lovely swap in place of the walnuts. Feeling particularly nutty? You can use a half measure of both walnuts and pecans in this cake if you can't decide between the two.

How to brown butter

Set a skillet over medium heat. Add butter and allow to melt, stirring with a wooden spoon occasionally.
As the butter melts it will begin to foam. Watch the pan closely during this process as the color will quickly change from buttery yellow, to golden, to toasty brown.
Once the butter has reached a stage where it is golden brown, remove it from the stove immediately and carefully transfer to a heatproof bowl.

What tools do I need to make this recipe?

A kitchen scale (or measuring cups for less accurate measurements)
Measuring spoons
A large mixing bowl
A medium mixing bowl
A hand mixer
A silicone spatula
A vegetable peeler
A traditional grater
A citrus zester
Optional: A chef’s knife and a cutting board — OR — a nut chopper, if your nuts are not pre-chopped
A 13 x 9 cake pan -- OR -- (2) 9-inch round cake pans
Parchment paper
A probe thermometer
A skillet
A fine mesh strainer (for sifting)
An offset spatula (for frosting)

Are you looking to upgrade to your cooking tools or replenish your pantry? Check out my kitchen tools shop page and pantry staples shop page to find my must-have kitchen tools, pantry items, and other Whip & Wander favorites.

Can I use another size pan for this Sourdough Discard Carrot Cake recipe?

I've tested this Sourdough Discard Carrot Cake using a 13 x 9-inch rectangular pan and (2) 9-inch round cake pans. For the 13 x 9-inch rectangular pan, I found that the cake needed about 60-minutes of baking time. When it was split between (2) 9-inch round cake pans, they only needed 35-40 minutes of baking time. You can, of course split the batter between (3) 9-inch cake pans if you prefer a taller cake, though I would start checking for doneness at the 20-25-minute mark.

Looking for more sourdough discard baking inspiration?

Love this Sourdough Discard Carrot Cake recipe? Here are some additional baking recipes that utilize sourdough discard that you might enjoy:

Sourdough Discard Carrot Cake with Browned Butter Cream Cheese Frosting

Author: Whip & Wander
Prep Time: 35 minutes
Cool Time: 2 hours
Cook Time: 60 minutes
Total Time: 3 hours 35 minutes
Yield: 15 servings 1x
Category: Desserts
Method: Oven / Stovetop
Cuisine: American

Print Recipe

Description

Ingredients

Scale

For the sourdough discard carrot cake:

240 g (2 cups) all-purpose flour
1 tbsp ground cinnamon
¼ tsp ground nutmeg
¼ tsp ground cloves
1 tsp Kosher salt
2 tsp baking soda
400 g (2 cups) white granulated sugar
8 oz (1 cup) canola oil or vegetable oil
250 g (1 cup) unsweetened applesauce
zest of 1 orange
2 tsp vanilla extract
4 large eggs
270 g (1 cup stirred down) 100% hydration sourdough discard
1 lb carrots, shredded (use freshly-shredded carrots, not pre-shredded)
100 g (1 cup) roughly chopped walnuts (may sub for pecans), optional
80 g (½ cup) seedless raisins, optional
Butter, for greasing pan

For the brown butter cream cheese frosting:

4 oz (1 stick) unsalted butter
8 oz (1 block) full-fat cream cheese, softened
1 tbsp orange juice
1 vanilla bean, seeded or 1 tsp vanilla bean paste
¼ tsp Kosher salt
8 oz (about 1 ¾ cups) confectioner's (powdered) sugar

Instructions

For the sourdough discard carrot cake:

Preheat the oven to 350 degrees F / 177 C. Line a 13 x 9-inch cake pan with pan (or (2-3) 9-inch cake pans depending on your preference) with parchment paper. Grease the parchment paper and any visible inner sides of pan with butter. Reserve to the side.
In a large bowl, combine the flour, cinnamon, nutmeg, cloves, salt, and baking soda. Whisk to combine. Reserve to the side.
In another large bowl, combine the sugar, canola oil, applesauce, orange zest, and vanilla. Using a whisk or a hand mixer, whisk or blend until well combined. Then add the eggs and whisk or blend again until well combined.
Add the sourdough discard to the wet ingredients, and using a silicone spatula, gently fold into the wet batter until well-combined. You do not want to overwork the sourdough discard or your crumb will not be as tender.
Add the dry ingredients to the wet ingredients. Using a silicone spatula, gently fold the dry ingredients into the wet ingredients for a couple of turns (there should still be some major flour steaks at this point). Then add the shredded carrots, and (if using) the nuts and raisins. Continue folding the ingredients until they are just combined, with no remaining flour streaks.
- The reason you want to add the carrots, nuts, and raisins in before the flour has been completely worked into the batter is for two reasons: 1. That the small amount of coating from the flour will help keep these heavier ingredients from falling to the bottom of the cake when baked, and 2. that the batter does not get overworked by mixing those ingredients in after the flour has been completely folded in.
Pour the batter into your cake pan (or evenly among your multiple smaller cake pans) and transfer to the oven. If using a 13 x 9-inch pan, the cake will need about 60 minutes of baking time. If using (2) 9-inch cake pans, the cake will need about 35-40 minutes of baking time. If you split the batter between (3) 9-inch cake pans, I would start checking for doneness at the 20-25-minute mark.
To check that the cake has baked, first look for visual cues. The top should be nicely golden and the edges of the cake should have pulled away from the sides of the pan just slightly. I like to gently press the top and see if it springs back. If the cake is nice and squishy it’s a good indicator that the cake is fully baked. If it’s still jiggly or your fingertips leave dents, it’s an easy indicator that it’s not done yet. The next thing I like to do is to take the internal temperature of the cake. For dense cakes like carrot cake, you’re looking for an internal temperature between 200-210 degrees F / 93-99 C. This is the thermometer I use in my kitchen.
- One popular way to test a cake’s doneness is to insert a toothpick or skewer into the cake and if it comes out with batter or crumbs it’s recommended that you continue to bake further. However, because carrot cake is so moist and dense this is not a great indicator for checking its doneness. Though you definitely want to continue baking is you see liquid batter, a few crumbs on the toothpick or skewer are totally normal. If you continue baking until you see no crumbs, you’re likely to overbake the carrot cake.
Allow the cake(s) to cool completely before frosting, at least 2-3 hours.

For the brown butter cream cheese frosting:

Brown the butter. Set a skillet over medium heat. Add butter and allow to melt, stirring with a wooden spoon occasionally. As the butter melts it will begin to foam. Watch the pan closely during this process as the color will quickly change from buttery yellow, to golden, to toasty brown. Once the butter has reached a stage where it is golden brown, remove it from the stove immediately and carefully transfer it to a large heatproof bowl to cool. I like to allow the butter to cool to room temperature before continuing because it helps yield a thicker, creamier frosting. However, if you want a thinner, slightly more icing-like frosting you can let the butter cool for a few minutes and then proceed.
Once the butter has cooled, add the cream cheese to the bowl, and using a hand mixer, blend the butter and cream cheese together until reasonably smooth. Then add the orange juice, vanilla bean seeds (or vanilla bean paste), and salt and blend again until smooth. Finally, sift the powdered sugar into the bowl and blend again until smooth and fluffy. I like to use an offset spatula to frost my cake once cooled.

*Leftover cake should be refrigerated and should keep for up to 3 days when stored in an airtight container in the fridge or 3 months when stored in an airtight container in the freezer.

Notes

Nutritional information on Whip & Wander is provided as a courtesy and is approximate only. We cannot guarantee the accuracy of the nutritional information given for any recipe on this site.

Nutrition

Serving Size: 1 serving
Calories: 623
Sugar: 49 g
Sodium: 313 mg
Fat: 32 g
Saturated Fat: 9 g
Carbohydrates: 71 g
Fiber: 3 g
Protein: 7 g
Cholesterol: 81 mg

Keywords: carrots, cake, cream cheese, brown butter, vanilla bean, walnuts, raisins