1 cup plus 2 tablespoons unsweetened cocoa powder*
2 and 1/4 cups all-purpose flour
2 and 1/4 cups sugar
2 and 1/4 teaspoons baking soda
1 teaspoon baking powder
1 teaspoon salt
3 large eggs
1 cup plus 2 tablespoons warm water
1 cup plus 2 tablespoons buttermilk
4 1/2 tablespoons safflower oil
1 1/2 teaspoons pure vanilla extract
For Frosting:
2 sticks unsalted butter, softened
1/2 cup cocoa powder*
3 cups powdered sugar
1/2 cup semi sweet chocolate chips, melted and cooled slightly
1/2 teaspoon vanilla extract
3-4 tablespoons milk or cream
Chocolate chips or shavings for garnish*
Instructions
For the cake:
Preheat the oven to 350 F. Butter two 8 or 9 inch round cake pans, sprinkle with flour and line with parchment rounds. Set aside.
In a large bowl combine all the dry ingredients (flour, sugar, cocoa powder, baking powder, soda and salt.) Whisk together until well combined.
Add all the rest of the ingredients- (eggs, buttermilk, warm water, oil and vanilla,) and whisk until smooth, clump-free and glossy. (Don't over-mix)
Divide the batter evenly among the pans, and bake for 30-40 minutes, (depending on your oven,) or until a cake tester inserted into the center comes out clean. Cool completely before frosting.
For the Frosting:
In a medium-large bowl, combine the butter, powdered sugar and cocoa and mix with an electric mixer until the dry ingredients have been worked into the butter, and the mixture is thick and paste-like. Fold in the melted chocolate and then add the extract and 3 tablespoons of milk or cream and mix on high speed until smooth and fluffy. At this point, create thicker or thinner frosting by adding more milk/cream or powdered sugar as needed.
Frost and layer cake as desired.
Notes
* I used dark dutch-process cocoa for both the cake and the frosting. Regular cocoa with work just fine though if that's what you have.