Sourdough Discard Carrot Cake (Made in One Bowl!)

This moist Sourdough Discard Carrot Cake is a great way to use your sourdough starter and bake it into a sweet treat! Slather this cake with your favorite cream cheese frosting for a tangy treat!

If you love this recipe, I think you'll love this sourdough apple cake and sourdough pumpkin cake too!

Sourdough breads are some of my favorite recipes to make, but did you know you could make sourdough desserts with your starter too? To reduce waste, I love adding my sourdough discard to a lot of my recipes.

This cake is so moist and perfect for the Spring. It is based off a recipe my family has been using for years, similar to my Instant Pot Carrot Cake which is always a hit! Even though this is a dessert, it's also my kids favorite way to eat carrots!

Why You'll Love This Recipe

• It's a great use for your sourdough discard! If you bake a lot, you'll likely have a lot of sourdough discard in the refrigerator. Use it to make sourdough Irish soda bread or sourdough discard banana bread. I've also compiled a huge list of sourdough discard recipes you'll love!
• It's a twist on the classic! Carrot cake is a classic recipe often served in the Spring. It's full of shredded carrots, some sort of nuts, sometimes raisins, and somethings fruit. This one has sweet pineapple and crunch walnuts, along with the tangy sourdough discard. Just like sourdough chocolate cake, adding sourdough discard to classic recipes is fun and delicious!
• It's made all in one bowl! No need to break out the heavy kitchen equipment, this recipe is mixed in one bowl and baked. It's so easy to make!

What is Sourdough Discard?

When people refer to sourdough discard, you may be thinking, what exactly is sourdough discard? Sourdough discard is the portion of your sourdough starter that you are not feeding. When you are "feeding" your starter to make Dutch oven sourdough bread with, you add equal parts flour, water, and starter to a mason jar and let it rise.

You can't feed your entire starter, as it doubles and sometimes triples in size, and that's a lot of starter to have on hand! If you are new to sourdough, be sure to check out how to feed and maintain a sourdough starter post all about how to keep your sourdough starter happy.

Ingredients to Gather

• Sourdough starter. You'll want your sourdough starter to be inactive and straight out of the refrigerator. If you are new to sourdough, you can make your own sourdough starter, buy one, or get one from a fellow sourdough friend.
• Flour. All purpose flour is great in this recipe. You can use bread flour if you prefer since there isn't much of a difference when it comes to baking cake.
• Sugar. We'll be adding both brown sugar and granulated sugar in the batter. Coconut sugar can be used in the batter if you prefer.
• Leavening agents. Even though we are using sourdough discard, it isn't active, so it won't add much rise to the cake. Baking soda and baking powder will do all the hard work to give this cake a nice rise.
• Oil. A neutral oil is best. A neutral oil would be vegetable oil, canola, oil, or my favorite, avocado oil.
• Carrots. This is a carrot cake after all! You'll want 2 cups shredded, which is about 3 large carrots. A box grater is easy to shred carrots, but I like using my food processor to make quick work of shredding the carrots.
• Mix ins. We'll be adding crushed pineapple for some added sweetness and chopped walnuts for some texture in the cake. Chopped pecans are a great choice too. Save the pineapple juice to make sourdough Hawaiian rolls too!

Be sure to check out the printable recipe card for full recipe information on ingredients and quantities.

How To Make Sourdough Discard Carrot Cake

Step 1: Preheat the oven to 350 degrees F. Grease a 9x13 inch baking dish or line it with parchment paper. In a large mixing bowl, add the sugars, oil, and eggs. Mix well until the ingredients are light and fluffy. Add the sourdough discard and mix until well combined.

Step 2: Add the flour, baking powder, baking soda, salt, and cinnamon. Mix until just combined, do not overmix the ingredients.

Step 3: Fold in the shredded carrots, pineapple, and walnuts.

Step 4: Pour the cake batter into the prepared baking dish. Bake for 45-50 minutes or until a toothpick is inserted and comes out clean. Allow the cake to cool before icing.

How To Make Cream Cheese Frosting

Serve this carrot cake with 3 ingredient cream cheese frosting for a super easy recipe, but you can also make your own homemade cream cheese frosting quickly.

1. Place the 1 stick of room temperature butter and 8 ounces of room temperature, full fat cream cheese in a medium bowl and mix together with a hand mixer. A stand mixer is also a great option to mix this frosting with.
2. Add 2 cups of powdered sugar, 2 tablespoons of milk, and 1 teaspoon of vanilla extract to the bowl and mix until you reach your desired consistency. Make sure to scrape down the sides of the bowl as the frosting is mixing.
3. If the icing is too thin, add more powdered sugar a tablespoon at a time. If the icing is too thick, add more milk, one tablespoon at a time.

Tips and Tricks

• To long ferment this sourdough batter, mix the ingredients together (except the baking soda and baking powder) and then cover the bowl with plastic wrap.  Place it in the refrigerator to long ferment the batter.  When you are ready to bake it, mix in the baking powder and baking soda, pour the batter into a greased 9x13 inch baking dish and bake for 45-50 minutes.
• This is a thick batter because of all the add ins. Don't stress if the batter is a little thicker than usual cake batter.
• Change up the cake pans! This sourdough carrot cake can be baked in a 9x13 inch baking dish.  It would also work perfectly in a Bundt cake or two 8 inch baking dishes.  Just make sure to properly grease the cake pans before baking.

How To Tell When Carrot Cake is Done Baking

There are a few tricks to tell when carrot cake is done. This is a very moist cake, so you will likely not get a completely dry toothpick if you use a toothpick to test for doneness.

• First, take a look at the cake. The cake should have a golden-brown color on the top, and the edges should be slightly pulling away from the sides of the pan.
• If you do use a toothpick to check for doneness, it's ok if there are a few crumbs left on the toothpick. It won't be completely dry. If it is completely dry, it's likely that the cake is overbaked.
• Do the spring back test! Gently press the center of the cake with your fingertip. If it springs back and doesn't leave an indentation, it's likely done.
• For the most accurate way to tell if the cake is done, you can use a kitchen thermometer. The internal temperature of the cake should be around 205-210°F (96-99°C) when fully baked.

Storage Info

You can make this cake up to 48 hours in advance. Cover the baked cake with plastic wrap once it has cooled to room temperature. Right before you are ready to serve it, frost the cake.

Keep leftovers in an airtight container or covered with plastic wrap in the refrigerator.

You can freeze the baked cake too! Once it is baked and cooled to room temperature, cover the cake with plastic wrap and aluminum foil and place it in the freezer for up to 3 months.

Sourdough Discard Carrot Cake FAQs

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