Gluten Free Sourdough Chocolate Cake (Sourdough Discard Recipe)

This gluten free sourdough chocolate cake is a unique twist on the traditional gluten free chocolate cake, incorporating gluten free sourdough starter into the batter to add depth of flavor and moisture. If you have never tried to bake with sourdough discard, this sourdough cake recipe is the perfect recipe to try. It's not only delicious but also made with simple ingredients and has very little prep time. Topped with a rich dark chocolate frosting, this one-bowl chocolate layer cake is the perfect everyday cake.

Recipe Ingredient Notes

Gluten Free Flour: I have tested this Gluten Free Sourdough Chocolate Cake successfully with my homemade gluten-free flour blend, Bob's Red Mill 1-to-1, and King Arthur Measure for Measure. Each flour blend produces a beautiful, light crumb. I am not saying other gluten free flour blends won't work in this application. I just didn't try them to make this recipe.

Gluten Free Sourdough Discard: Sourdough discard refers to a portion of the gluten free sourdough starter that is removed and discarded during the feeding process. You will need unfed gluten free sourdough starter for this sourdough discard chocolate cake recipe. The added sourdough starter discard not only provides moisture but also adds a delicious depth of flavor to this cake.

Cocoa Powder: I recommend using a dutch processed cocoa which produces a rich chocolate flavor in this sourdough chocolate cake. While my personal favorite is deZaan cocoa powder, I really like using Hershey Special Dark for quick bakes like this one bowl chocolate cake.

Neutral Oil: Oil tends to produce a lighter and airier texture in cakes compared to butter. This is because oil is a liquid at room temperature. It coats the flour particles more evenly, resulting in a finer crumb structure. This can lead to a softer, more delicate chocolate cake. A neutral oil such as vegetable oil or grapeseed oil will work just fine. I do not use coconut oil in my baking.

Hot Coffee: Coffee has a rich and deep flavor that complements the taste of chocolate. When added to a chocolate cake recipe, it can intensify and enhance the overall chocolate flavor, making the cake more decadent and delicious. The bitterness of coffee also balances out the sweetness of the chocolate and sugar in the cake, creating a well-rounded flavor profile. If you prefer to keep this dessert coffee free, please substitute with hot water.

Sour Cream Frosting: I use a half patch of my Dark Chocolate Sour Cream Frosting to finish this Chocolate Sourdough Discard Cake. Its rich with a little tang from the sour cream which pairs wonderful with this cake. I use regular unsalted butter but the frosting can be made with dairy free butter and dairy free sourcream.

What is Sourdough Discard?

Sourdough discard refers to a portion of a sourdough starter that is removed and discarded during the feeding process. Sourdough starters are mixtures of flour and water that capture wild yeast and bacteria from the environment, allowing for the fermentation of dough in bread baking. To maintain a healthy and active sourdough starter, it needs to be regularly fed with fresh flour and water.

During the feeding process, a portion of the existing starter is removed before adding new flour and water. This discarded portion is known as the "discard." While it's called "discard," it doesn't necessarily mean it needs to be thrown away. It can be repurposed in recipes like this gluten free sourdough discard chocolate cake rather than wasting it. It adds a tangy flavor to the baked goods and can be a way to reduce waste while enjoying the benefits of sourdough fermentation.

Why add Sourdough Discard to Chocolate Cake

Adding sourdough discard to this gluten free one-bowl chocolate cake can bring several benefits to the final product.

Flavor enhancement: Sourdough discard contributes a mild tangy flavor due to the fermentation process. This tanginess can complement the sweetness of the chocolate, creating a more complex and interesting flavor profile in the chocolate cake.

Moisture: Sourdough discard contains water, and adding it to the cake batter can contribute moisture. This can result in a more tender and moist gluten free chocolate cake.

Leavening agent: While sourdough discard is not as potent as a fully mature and active sourdough starter, it still contains some wild yeast and lactic acid bacteria. These can provide a mild leavening effect to this one-bowl chocolate cake, leading to a slightly lighter and airier texture. Which is always a big plus when it comes to gluten free baking.

How to make a Sourdough Chocolate Cake

I like to use a 9" spring form to make this gluten free one-bowl chocolate cake. An 8x8 or 9x9 square pan can also be used. I don't recommend using an 9x13 pan since the cake will be very thin (unless you double the recipe)

Step 1: Preheat the oven to 350F. Lightly spray the spring form with nonstick cooking spray and line the bottom with parchment paper. Set aside.

Step 2: Combine the gluten-free multi-purpose flour, cocoa powder, baking powder, baking soda and kosher salt. Make sure to sift or stir it together. Especially if the cocoa powder appears to be lumpy.

Step 3: In a large mixing bowl combine the granulated sugar, oil and room temperature eggs. Mix together until combined.

Step 4: Add the unfed sourdough discard and vanilla extract to the mixture and whisk together until smooth. My sourdough discard has the consistency of warmed up peanut butter. Sourdough discards can have different textures and consistencies depending on which flour you use (I use a mix of Sorghum and Fine Brown Rice Flour)

Step 5: Retrieve the bowl with the dry ingredients and add them to the wet ingredients. Mix everything together with a whisk or a spatula until the batter is smooth and well combined.

Step 6: Gradually pour the hot coffee or hot water to the batter, stirring continuously. The batter will become thin, but that's normal.

Step 7: Transfer the gluten free sourdough chocolate cake batter to the prepared cake pan. With a small offset knife or the back of a spoon, smooth it out evenly.

Step 8: Bake the chocolate sourdough cake at 350F for 35-40 minutes or until a toothpick inserted into the center of a cupcake comes out clean. The top of the cake should feel bouncy to the touch. Be mindful not to overbake, as this can dry them out. Baking times depend on the oven and the baking pan used.

Step 9: Remove the chocolate cake from the oven and allow for it to cool on a cooling rack for 10-15 minutes before removing it from the cake pan. Cool the cake completely on the wire rack before frosting. If your cake is sticking to the cake pan, carefully run a butter knife around the edges to loosen it.

Dark Chocolate Sour Cream Frosting

I use a half batch of my Dark Chocolate Buttercream Frosting to finish this gluten free one-bowl chocolate cake. If chocolate is not your thing, this cake would also be delicious with Salted Caramel Buttercream, a Peanut butter frosting or even a cream cheese frosting.

This frosting can be made with a stand mixer using the paddle attachment or in a large bowl using an electric hand mixer.

To make the chocolate frosting, bring a medium saucepan filled with 1 inch of water to a simmer. Add the bittersweet chocolate to a heatproof bowl and set the bowl over—not in—the simmering water to melt the chocolate; let cool slightly.

In a large bowl, using an electric mixer, beat the room temperature butter and kosher salt at medium speed until smooth for at least 5-7 minutes. Beat in a teaspoon vanilla extract and the melted chocolate until fully incorporated. Beat in the powdered sugar one-third at a time, scraping down the bowl between additions. Using a rubber spatula, fold in the sour cream until no white streaks remain.

Once the gluten-free sourdough chocolate cake is completely cold, transfer it to a serving platter and frost the top with a generous layer of the dark chocolate sour cream frosting.

Garnish with some gluten free sprinkles, chocolate shaving, mini chocolate chips toasted nuts or whatever your heart desires.

Allow the cake to set up in the fridge for 10 minutes before slicing and serving. I recommend using a sharp, hot knife to slice the cake. Dip your Chef’s Knife in the hot water and dry very well with the towel. The hot water will warm up the blade and will slide through the frosting and the one-bowl chocolate cake a lot easier. Clean your knife in between cuts in the hot water, wipe clean, and continue cutting. The cleaning is the very important part here. If you skip this step, you're going to smudge all the leftovers from your previous cut onto the next cut.

Storage & Freezing

I recommend storing this gluten free one-bowl chocolate cake in an airtight container at room temperature for up to 3 days or up to 5 days in your refrigerator. This cake is actually better the second day once the flavors have fully developed. If you choose to store the cake in the refrigerator, make sure to let it sit at room temperature 15-20 minutes before serving.

Freezing the unfrosted gluten free chocolate cake is very simple. Before freezing, make sure the chocolate cake has cooled completely. If it's warm, condensation can form inside the packaging, leading to freezer burn. Wrap the entire cake tightly in plastic wrap. Ensure that the plastic wrap covers the entire surface of the cake to prevent air from reaching it. For added protection, place the wrapped cake in an airtight container. This helps prevent the cake from absorbing any odors from the freezer. Freeze the cake up to 2 months. When you're ready to enjoy the cake, remove it from the freezer and let it thaw in the refrigerator. Thawing in the fridge helps prevent condensation and ensures a more even thaw. Frost the thawed cake with your frosting of choice and serve.

Leftover slices of the cake can be frozen in an airtight container up to one month. When ready to eat, thaw the slice at room temperature.

FAQ - Sourdough Chocolate Cake

Note about Salt in my Recipes

I use Diamond Kosher Crystal Salt in all of my recipes unless otherwise stated. If use use a different brand or kind of salt in your kitchen please adjust accordingly since some salts can be saltier. If you use Morton’s Kosher Salt please be aware that their salt granules are smaller in size, denser, and crunchier and twice as salty.

Baking in grams

I share my recipes in grams and by weight since baking by weight is the most accurate way to bake. Digital Scales are very affordable and easy to use. You can purchase them on Amazon for less than a set of measuring cups. For small amounts under 10 grams, I like to use this Precision Pocket Scale. Measuring cups are very inaccurate which can cause significant errors when it comes to gluten-free baking or baking in general. Especially since I bake with gluten-free flours which weigh differently than “regular” flours. I do provide some ingredients like spices and leavening agents in measuring spoons. To learn more about Baking with a digital scale, make sure to check out my post about Baking by weight.

Note about Ovens and Oven Temperatures

All my recipes are tested and developed with a conventional oven. I always bake my baked goods on the rack placed in the MIDDLE of my oven. This way the heat coming from the bottom will not burn my baked goods.

If you are baking with convection (fan-forced), please adjust the recipes accordingly. Convection oven can cause baked goods to dry out quickly and still be raw inside. Since takes at least 15-20 minutes for a standard American Oven to be fully preheated. I highly recommend investing in an Oven Thermometer.

Substitutions and Modifications

Any dietary or ingredient modifications/substitutions to this recipe may alter the end result in appearance and taste. I test my recipes several times as published in this post and The Gluten Free Austrian Blog is not responsible for the outcome of any recipe you find on our website.