Ingredients :
1 3/4 cups (230g) all-purpose flour
1/4 cup (30g) cornstarch
1 cup (100g) unsweetened cocoa powder
2 teaspoons baking soda
1 teaspoon baking powder
1/2 teaspoon kosher salt
1 cup (200g) granulated sugar
1 cup (205g) dark brown sugar, firmly packed
1/2 cup (108g) vegetable oil
1 cup (230g) mayonnaise
3 whole eggs plus 1 egg yolk
1/2 cup (128g) milk
1 tablespoon vinegar
2 teaspoons vanilla extract
1 cup (240g) hot coffee (or 1 cup hot water mixed with 2 teaspoons instant espresso powder)
For the Chocolate Fudge Frosting :
2 cups (450g) unsalted butter, at room temperature
1 1/2 cups (165g) powdered sugar
3 tablespoons corn syrup
1 teaspoon vanilla extract
A pinch of kosher salt
3/4 cup (177g) warm water
3/4 cup (75g) Dutch process cocoa powder (or unsweetened cocoa powder)
10 oz dark chocolate chips (one bag), melted and slightly cooled
Instructions :
Chocolate Cake Preparation:
Preheat your oven to 350°F (177°C) and prepare three 8-inch cake pans by greasing the insides and lining the bottoms with parchment paper. Optionally, wrap the pans with damp cake strips.
Whisk together the flour, cornstarch, cocoa powder, baking soda, baking powder, and salt in a medium bowl. Set aside.
Combine the milk, vinegar, and vanilla in a measuring cup. Set aside.
In a large bowl, whisk the sugars, oil, and mayonnaise until well combined. Mix in the eggs and egg yolk.
Stir in the milk mixture, then gradually mix in half of the dry ingredients until combined. Add the hot coffee, whisking well, followed by the remaining dry ingredients, resulting in a thin, liquid batter.
Divide the batter evenly among the prepared pans.
Bake for 30-35 minutes or until a toothpick inserted in the center comes out clean with a few crumbs attached.
Allow the cakes to cool in the pans for about 10 minutes before running a knife around the edges and turning them out onto a wire rack to cool completely.
For the Chocolate Fudge Frosting :
As the cakes bake, begin the frosting by beating the butter until smooth.
Mix in the powdered sugar, corn syrup, vanilla, and salt.
Dissolve the cocoa powder in the warm water and add to the frosting, mixing until combined.
Stir in the melted chocolate until the frosting is smooth and glossy.
If needed, refrigerate the frosting for about 45 minutes to thicken.
Once chilled, stir the frosting until it’s ready to spread.
Assembling the Cake :
Ensure the cake layers are cool and level the tops if necessary.
Start with one layer on a cake turntable, spreading frosting on top, then stacking the next layer and repeating the frosting.
After stacking, chill the cake for 20 minutes to set the layers before covering the entire cake with frosting.
Once frosted, let the cake set in the refrigerator before serving.
Slice and enjoy this decadent chocolate masterpiece !