Quick Sourdough Discard Mug Cake Recipe

This quick and easy sourdough discard mug cake is the perfect small-batch dessert when you want something warm, chocolatey, and satisfying in minutes. Made in the microwave, this single-serving chocolate cake uses sourdough discard, simple pantry ingredients, and no egg. It is ideal for a fast dessert after dinner, a sweet afternoon pick-me-up, or a cozy mid-morning treat with a hot cup of coffee.

Think of it as a miniature sourdough chocolate cake made in a mug. The sourdough starter adds moisture and gives the cake a soft, velvety texture without making the flavor too tangy, as long as your discard is fresh. You can make this sourdough discard mug cake with dairy milk or plant-based milk, so it is easy to adapt if you prefer a vegan version.

This recipe is especially useful when you have a small amount of sourdough discard to use up and do not want to bake a full cake. Serve it straight from the mug with a scoop of vanilla ice cream, a spoonful of double cream, powdered sugar, or a little extra chocolate on top. It is simple, comforting, and ready in less than 10 minutes.

If you enjoy quick sourdough recipes, this chocolate sourdough mug cake is a great one to keep on hand. It uses everyday ingredients, requires very little cleanup, and can be customized with jam, peanut butter, caramel, chocolate chips, or fresh fruit.

Using Sourdough Discard in a Cake

This sourdough discard mug cake uses 40 g of sourdough discard for one serving. You can also use active sourdough starter if that is what you have available. Either option works well, provided the starter is not overly sour.

For the best flavor, use fresh sourdough discard that has not been sitting for too long. Discard that is more than 24 hours old may have a stronger tang, and that sour flavor can dominate the chocolate cake. If your discard is a little older, smell it first and use your judgment. A mild, pleasantly fermented aroma is fine, but a sharp or overly acidic smell may not be the best choice for this recipe.

The sourdough discard helps create a moist, tender crumb while also reducing waste. Because the cake is cooked quickly in the microwave, it will not taste like a long-fermented sourdough bake. Instead, the starter blends into the batter and supports the rich cocoa flavor.

How To Make Sourdough Discard Mug Cake

This microwave sourdough mug cake could not be easier to make. You do not need a separate mixing bowl if you are making one serving; simply mix the batter directly in the mug. If you are making two or more cakes, it can be easier to combine the batter in a small bowl first and then divide it between mugs before cooking.

Use a microwave-safe mug with enough room for the cake to rise. A 400 ml or 13.5 oz mug works well because it gives the batter space to expand and leaves room for toppings after cooking.

1. Add the flour, cocoa powder, sugar, baking powder, and salt to the mug. Stir well so the dry ingredients are evenly combined and there are no pockets of cocoa or flour.
2. Add the milk, oil, sourdough starter, and vanilla extract, if using. Mix thoroughly until the batter becomes smooth, glossy, and chocolatey. Scrape around the bottom edges of the mug so no dry ingredients remain.
3. If you would like a filling, add a teaspoon of raspberry jam, peanut butter, caramel sauce, or another favorite addition to the top of the batter. Gently push it down until it is just covered.
4. Microwave the mug cake on high power for 2 minutes. The cake is ready when it has risen and feels firm to the touch. Take care when removing the mug from the microwave, as it will be very hot.
5. Dust with powdered sugar and serve immediately with vanilla ice cream, double cream, or your favorite topping.

Ingredient Notes

• All-purpose flour is the best choice for this sourdough discard mug cake. Self-rising flour can be used, but leave out the baking powder if you make that substitution to prevent the batter from overflowing.
• White granulated sugar gives a simple, classic sweetness. Brown sugar, coconut sugar, or maple syrup can also be used, although the texture and flavor may vary slightly.
• Unsweetened cocoa powder gives the cake its rich chocolate flavor. Raw cacao or Dutch-processed cocoa may also be used.
• Whole milk works well, but any milk is suitable, including plant-based milk. Because the recipe is egg free, using plant-based milk makes this a vegan sourdough mug cake.
• Vegetable oil keeps the cake moist and soft. Use a light-flavored oil so it does not overpower the chocolate. Coconut oil also pairs nicely with cocoa if you enjoy that flavor.
• Vanilla extract is optional, but it rounds out the chocolate flavor and makes the cake taste more like a classic dessert.

Flavor Variations for Sourdough Discard Mug Cake

This chocolate sourdough discard mug cake is delicious as written, but it is also easy to customize. Try one of these simple additions to change the flavor and make it feel like a new dessert each time.

• Stir a few tablespoons of chocolate chips into the batter. White chocolate, milk chocolate, dark chocolate, or semi-sweet chocolate chips all work well.
• For a lava-style center, press a few small squares of chocolate into the middle of the batter before microwaving.
• Add a teaspoon of jam, such as raspberry, strawberry, or blueberry, for a fruity center that pairs beautifully with chocolate.

• For a caramel version, add caramel sauce to the batter just before cooking, or press a small caramel candy into the center.
• Sprinkle grated chocolate over the hot cake before serving so it melts slightly on top.
• Add a spoonful of peanut butter for a rich chocolate-peanut flavor.
• Top the finished cake with powdered sugar, cream, ice cream, or fresh berries.

Can You Store This Sourdough Mug Cake?

This sourdough mug cake is best cooked and eaten straight away. Like most microwave mug cakes, the texture is at its best when warm and freshly made. If left to sit for too long, it can become dense or stodgy.

Because the recipe makes one small portion, there is usually no need to store leftovers. It is a convenient dessert for one person and a practical way to use a small amount of sourdough discard without wasting ingredients.

Frequently Asked Questions