This sourdough chocolate cake recipe isn’t just useful for using up sourdough discard, it also yields an incredible, fudgy and moist chocolate cake that will rival any bakery cake (and perhaps even any cake you’ve ever tasted before — seriously!). Recipe includes a silky-smooth, not-too-sweet chocolate frosting and a video tutorial.
Sourdough Discard Chocolate Cake
Somehow both remarkably decadent yet not too sweet, my sourdough chocolate cake is my favorite way to use up sourdough discard. The chocolate crumb is melt-in-your mouth with just the right amount of stick-to-your-fork fudginess. The chocolate flavor shines while the sourdough adds a lovely depth of flavor… and wait til you try the frosting I like to pair it with!
Why it works:
- Utilizes sourdough discard for perfect depth of flavor (while also cutting down on waste!).
- Hot water (or coffee) makes a difference. It blooms the cocoa (creating rich chocolate flavor), adds moisture to the cake for unparalelled fudginess, and fosters a moist, tender texture. If you opt for coffee rather than water, the chocolate flavor is enhanced even more (and you get a touch of bitterness — ideal for dark chocolate or coffee lovers).
- Based off my favorite chocolate cake recipe. A tried and trusted recipe carefully modified to perfectly incorporate (and benefit from) sourdough discard.
- Neither the cake nor the frosting feel too sweet. They’re very satisfying and still feel incredibly indulgent (I mean they are indulgent), but it’s not overkill.
- Perfected technique. My recipe uses a version of the reverse creaming method that is very simple to do and perfect for beginner bakers, since its nearly impossible to over-mix.
What You Need
For the Cake
- Sourdough discard. Try to let this come to room temperature beforehand, as it will incorporate into the batter much easier. If at all possible, weigh your discard instead of measuring it in a cup and don’t use discard that’s more than a day or two old (if you haven’t refrigerated it). The older your discard, the thinner and more pungent it becomes, and older discard can negatively affect your recipe.
- Natural cocoa powder. Stick with natural cocoa powder here, as you could have issues with rising if you use Dutch process cocoa. I talk more about the differences between the two in my post on natural vs Dutch process cocoa.
- Hot water or coffee. And it must be hot (boiling or steaming is perfect!) to “bloom” and bring out the flavor of the cocoa powder. Water works just fine, but coffee brings out the bitterness of the chocolate more (in a good way–this is a nice choice for dark chocolate and coffee lovers).
- Oil & butter. If you’ve made my triple chocolate cake or chocolate raspberry cake, you know that a blend of oil and butter is KEY for a crumb that’s both moist and flavorful. Oil adds the moisture while butter adds the flavor.
- Buttermilk. I prefer and recommend using real buttermilk here over my buttermilk substitute, but the substitute will work in a pinch (I generally use just slightly less, a tablespoon or so less, than called for).
For the Frosting
A bit different from the norm, this silky chocolate frosting uses a surprise ingredient (bottom left). It suits the cake perfectly without overpowering it.
- Sour cream. This might seem like a strange addition, but it works. It keeps the frosting from being too sweet, adds depth, and adds a wonderful silky texture.
- Cocoa powder. I prefer to use natural cocoa powder (which we’re already using in the cake itself).
- Salted butter. While I prefer unsalted butter in the cake itself, I reach for salted for the frosting. If you only have unsalted butter on hand, simply add ¼ teaspoon or so of salt in with the butter.
- Vanilla. While this is a chocolate frosting, a touch of vanilla complements and rounds out the flavor so nicely. Vanilla helps round out and enhance the chocolate flavor; I add vanilla to many of my chocolate desserts, like my chocolate pudding and chocolate cheesecake. Don’t skip it!
- Heavy cream. Just a splash adds to the silky texture. Double cream or whipping cream will also work here!
SAM’S TIP: Sometimes I swap out both sugars in the cake for organic sugar. It works great and has a great flavor.
Remember, this is just an overview of the ingredients I used and why. For the full recipe please scroll down to the bottom of the post!
How to Make Sourdough Chocolate Cake
Make the cake
- Whisk the dry ingredients and sugars together in a large bowl.
- Stir in the oil and butter until the mixture is evenly moistened–it will be very thick at this point.
- Add the buttermilk and stir well to incorporate, then stir in sourdough discard, eggs, and vanilla. Make sure the batter is cohesive.
- Carefully pour in the hot water and stir gently (don’t burn yourself with splashes!) until you have a smooth, uniform batter. It will be very thin at this point. Scrape the sides and bottom of the bowl to make sure you don’t have any lumps or dry pockets!
Divide and bake
- Divide the batter into two greased, floured, and lined cake pans. If you really want to be precise with this, use a kitchen scale to make sure each pan has the same amount of batter!
- Bake until a toothpick comes out clean or with a few moist crumbs, about 30-35 minutes.
- Let the cakes cool in their pans for a few minutes before inverting onto a cooling rack to cool completely.
Make the frosting
While I was tempted to top this cake with my favorite chocolate frosting, I ultimately opted for something a bit different here: a sour cream-infused twist on my chocolate buttercream. Sounds weird maybe, but a touch of sour cream keeps the icing from being too sweet and adds a silky texture that I adore (and think you will, too). Even if you’re not a sour cream fan, I suggest you try it! It’s less prominent (and less in amount) than cream cheese in cream cheese frosting.
- Cream the butter until smooth, then gradually add the powdered sugar with your mixer on low speed. Stir in the cocoa powder.
- Stir in the sour cream and vanilla, then drizzle in the heavy cream.
- Frost your cake as desired. I recommend doing a crumb coat with this recipe for the easiest decorating; to do this, simply stack and frost your cake with a very thin coating of frosting around the sides. Pop the entire thing in the fridge or freezer until firm, then continue frosting as normal.
- Slice and enjoy!
SAM’S TIP: This cake is a humble one with a simple frosting that’s difficult to mess up (simply smear it over the cake!). But if you’re interested in a slightly more sophisticated decorating technique, see my guide on how to decorate a cake. It’s perfect for beginners and everything I wish I’d known when I first started decorating cakes.
Frequently Asked Questions
Of course! You could use any one of my frosting recipes, though chocolate cream cheese frosting, raspberry buttercream, brown butter frosting or coffee frosting would be my top picks. Ooh, or my chocolate Swiss meringue buttercream!
This sourdough chocolate cake was specifically designed to incorporate sourdough discard. If you don’t have any on hand, try my chocolate cake recipe or devil’s food cake recipe (you won’t be disappointed!)
Or, if you want to start baking with sourdough, check out my post on how to make a sourdough starter! It’s a lot of fun, and you’re rewarded with tasty treats like sourdough cheddar jalapeno bread and sourdough donuts 😋
Any other sourdough discard recipes you’d like to see? Let me know in the comments! ⬇️
Enjoy!
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Sourdough Chocolate Cake
Ingredients
- 1 cup (125 g) all-purpose flour
- 1 cup (200 g) granulated sugar
- ¾ cup (150 g) light brown sugar firmly packed
- ¾ cup (75 g) natural cocoa powder
- 1 ¼ teaspoons baking soda
- ¾ teaspoon salt
- ½ cup (113 g) unsalted butter melted
- ½ cup (118 ml) neutral cooking oil (canola oil, vegetable oil, or avocado oil)
- ⅔ cup (160 ml) buttermilk (room temperature preferred)
- ⅔ cup (145 g) sourdough discard (room temperature preferred, see note)
- 2 large eggs room temperature preferred, lightly beaten
- 2 teaspoons vanilla extract
- ½ cup (118 ml) very hot water or coffee
Frosting
- 1 cup (226 g) salted butter softened (or use unsalted and add ¼ teaspoon salt)
- 3 cups (375 g) powdered sugar
- ⅔ cup (67 g) cocoa powder
- 3 Tablespoons (45 g) sour cream
- 1 ½ teaspoons vanilla extract
- 4 Tablespoons heavy cream
Recommended Equipment
Instructions
- Preheat oven to 350F (175C). Lightly grease and flour the sides of two 8” cake pans, tap out the excess flour, and line the bottoms with rounds of parchment paper. Set aside.
- In a large mixing bowl, whisk together flour, sugars, cocoa powder, baking soda, and salt until thoroughly combined.1 cup (125 g) all-purpose flour, 1 cup (200 g) granulated sugar, ¾ cup (150 g) light brown sugar, ¾ cup (75 g) natural cocoa powder, 1 ¼ teaspoons baking soda, ¾ teaspoon salt
- Add butter and oil and stir well until all ingredients are thoroughly moistened and combined (I do this by hand but it would be fine to use a mixer).½ cup (113 g) unsalted butter, ½ cup (118 ml) neutral cooking oil
- Add buttermilk and gently stir to combine. Add sourdough discard, eggs, and vanilla extract and stir well.⅔ cup (160 ml) buttermilk, ⅔ cup (145 g) sourdough discard, 2 large eggs, 2 teaspoons vanilla extract
- Carefully add hot water and stir well until batter is uniform and smooth and no lumps remain (batter will be thin, this is fine). Be sure to scrape down the sides and bottom of your bowl with a spatula to incorporate all ingredients.½ cup (118 ml) very hot water or coffee
- Evenly divide batter between prepared cake pans. Transfer pans to the center rack of 350F (175C) preheated oven and bake for 30-35 minutes, until a toothpick inserted into the center comes out clean or with a few moist crumbs.
- Allow cakes to cool in their pans for 10 minutes before running a knife along the edges to loosen the sides and then carefully invert onto cooling racks to cool completely before frosting.
Frosting
- In a large mixing bowl, use an electric mixer to beat butter until it is smooth and creamy.1 cup (226 g) salted butter
- With your mixer on low speed, gradually add powdered sugar, 1 cup at a time, stirring until fully incorporated.3 cups (375 g) powdered sugar
- Stir in cocoa powder (if batter is thick and difficult to stir, you can add the heavy cream a bit early to help loosen it up).⅔ cup (67 g) cocoa powder
- Add sour cream and vanilla extract and stir to combine.3 Tablespoons (45 g) sour cream, 1 ½ teaspoons vanilla extract
- With mixer on low speed drizzle in heavy cream until completely incorporated (be sure to scrape the sides and bottom of the bowl to make sure frosting is well combined).4 Tablespoons heavy cream
- Spread over cooled cakes, slice and enjoy!
Notes
13×9 pan:
Bake for 30-35 minutes on 350F (175C).Sourdough discard
It’s best to weigh the sourdough discard rather than use measuring cups as the volume of discard can vary (it gets heavier the longer it sits). Older discard will be more pungent and will impart a stronger flavor, and if you’re not weighing it you may accidentally end up using more than you need.Can I use active starter?
Yes, so long as you weigh it so you end up using the proper amount. If you don’t have a scale you could try stirring down the starter and then measuring it.Butter
I like using salted butter for the frosting, but if you only have unsalted you can simply add a pinch of salt to the frosting.Storing
Store in an airtight container at room temperature for up to 48 hours or in an airtight container in the refrigerator for up to 5 days.Nutrition
Nutritional information is based on third-party calculations and should be considered an estimate only. Actual nutritional content will vary based upon brands used, measuring methods, cooking method, portion sizes, and more.
Yolanda Mack
Absolutely delicious! I just made this chocolate cake and my family loves it. The only difference was that I used my homemade milk kefir instead of buttermilk because I didn’t have buttermilk on hand and I decided to use the hot coffee instead of hot water. Thank you so much Sam for sourdough recipes. Every sourdough recipe of yours that I have made has been a hit in my home and I keep making them over and over! Keep the sourdough recipes coming!!
Sam
I’m so glad everyone enjoyed the cake so much, Yolanda! Thank you for the feedback. 🙂