Sourdough Chocolate Cake

Let's Cook

1. Step 1.

   The night before baking (or at least 2 to 3 hours before starting the cake), in a medium bowl, mix together 1½ cups all-purpose flour, 1 cup water, ½ cup sourdough starter, and ¼ cup nonfat powdered milk until well combined. Cover the bowl and set it in a warm place (around 70-80°F) for 8-12 hours or overnight. The mixture should become bubbly and develop a clean, mild sour odor.

2. Step 2.

   In the morning, preheat the oven to 350°F. Grease and flour two 9-inch round cake pans or one 9-by-13-inch baking pan.

3. Step 3.

   In the bowl of a stand mixer fitted with the paddle attachment, cream together 1 cup sugar, ½ cup (1 stick) unsalted butter (softened), 1½ teaspoons baking soda, 1 teaspoon vanilla extract, 1 teaspoon ground cinnamon, and ½ teaspoon kosher salt on medium speed until light and fluffy, about 2-3 minutes.

4. Step 4.

   Add 2 large eggs one at a time, beating well after each addition until fully incorporated. Scrape down the sides of the bowl as needed.

5. Step 5.

   Add 3 ounces unsweetened baking chocolate (melted and slightly cooled) and the sourdough mixture to the mixer bowl. Mix on low speed or stir by hand for 300 strokes until the batter is smooth and evenly blended. Do not overmix.

6. Step 6.

   Divide the batter evenly between the prepared pans (or pour into the 9x13 pan). Bake for 25 to 30 minutes, or until a toothpick inserted into the center of the cake comes out clean. The cake should be springy to the touch.

7. Step 7.

   Allow the cakes to cool in the pans on a wire rack for 10 minutes, then turn them out onto the rack to cool completely before frosting. Once cool, frost the sides and top of the cake with Chocolate-Butterscotch Frosting using a butter knife.