Ingredients :
1-3/4 cups all-purpose flour
1-3/4 cups sugar
3/4 cup unsweetened cocoa
2 teaspoons of baking powder
1 teaspoon of baking soda
1/4 teaspoon of salt
2 large eggs room temperature
3/4 cup buttermilk or make your own with milk and vinegar, room temperature
1/4 cup sour cream at room temperature
1/3 cup vegetable oil
2 teaspoons of pure vanilla extract
3/4 cup boiling water
Chocolate Buttercream Frosting:
1 1/2 cups (3 sticks) unsalted butter at room temperature
4-5 cups sifted powdered sugar
3/4 cup sifted unsweetened cocoa powder
4 to 6 tablespoons of heavy cream depending on desired consistency
2 teaspoons of pure vanilla extract
1/8 teaspoon salt
Garnish (optional):
1-1/2 – 2 cups mini chocolate chips
Chocolate chips

Instructions
Preheat oven to 350 degrees F. Prepare three 6-inch or two 8-inch round cake pans by spraying with cooking spray, sprinkling with cocoa powder and shaking off excess. Line the bottom of the molds with parchment paper and set aside.
Using a hand mixer or stand mixer fitted with the paddle attachment, combine the flour, sugar, cocoa powder, baking powder, baking soda and salt. Mix on low for 30 seconds or until well combined.
Add eggs, buttermilk, sour cream, oil and vanilla. Beat on medium speed for about two minutes until smooth.

Reduce speed and slowly add boiling water to cake batter. Turn the mixer to high and beat for about 1 minute until the ingredients are incorporated.
Divide the cake batter evenly between the prepared cake pans. Bake for 30 to 35 minutes or until a toothpick or cake tester inserted in the center comes out clean.
Remove from oven and let cool for 15-20 minutes, remove from pan and let cool completely on a wire rack.
Make the frosting: Using a hand or stand mixer fitted with a paddle attachment, cream the butter on high speed until light and creamy, about 5 minutes.
Turn the mixer to low and slowly add the sifted cocoa powder and sifted powdered sugar 1 cup at a time. Beat until sugar/cocoa is combined.
Turn the mixer to medium speed and add the vanilla and cream 1 tablespoon at a time and beat until smooth.
Increase speed to high and beat for 1 minute. You may need to add more cream or more powdered sugar depending on your desired consistency or if you want to increase the thickness of the frosting. Taste and add salt to taste.
Assemble the cake: Place 1 layer, flat side up, on a plate or cake stand.
With a knife or offset spatula, spread the top with about 1/2 – 2/3 cup frosting.
Place the second layer evenly on top and press gently so that the cake layers adhere.
Spread another 1/2 – 2/3 of frosting evenly on top.
Place the third layer, bottom side up, on top of the frosted layer and add frosting to the top and sides of the cake with a very thin layer of frosting (the crumb layer).
Refrigerate the cake for about 15 minutes to let the crumb layer set up.
Frost the sides and top of the cake with the topcoat.
Decorate with chocolate chips or to taste.

Recipe Notes:
This recipe can also make an 8-inch or 9-inch two-layer cake.
The 8 inch cake will have taller layers.
The amount of frosting is enough to generously frost a 3-layer, 9-inch cake. You may have leftovers that can be stored in an airtight container in the refrigerator for up to 3 days or in the freezer for 3 months.
If the frosting seems too dry, add more cream, a tablespoon at a time until it reaches the right consistency. If it seems too wet and doesn’t hold its shape, add more powdered sugar, 1/4 cup at a time until it reaches the right consistency.
Cake recipe adapted from Hershey’s