Chocolate Cake

Ingredients

• •.75 cup neutral oil (like canola or grapeseed), plus more for greasing the pans
• •2.25 cups granulated sugar
• •2 cups all-purpose flour
• •1.25 cups cocoa powder, sifted if lumpy
• •1.5 teaspoons baking powder
• •1.5 teaspoons baking soda
• •1.5 teaspoons kosher salt (such as Diamond Crystal)
• •1.5 cups unsalted butter, softened to room temperature
• •3 large eggs
• •3.75 cups grams confectioners' sugar, sifted if lumpy
• •1.5 cups cocoa powder, sifted if lumpy
• •.25 cup sour cream
• •.25 cup lukewarm milk, plus more as needed
• •1 tablespoon vanilla extract
• •.75 teaspoon kosher salt (such as Diamond crystal)
• •Sprinkles (optional), for decorating

Instructions

1. 1Make the cake: Set a rack in the center of the oven and heat oven to 350 degrees. Generously grease two 9-inch baking pans and line the bottoms with parchment paper.
2. 2In a large bowl, combine the granulated sugar, flour, cocoa powder, baking powder, baking soda and salt. Whisk until well combined and no lumps remain
3. 3In a medium bowl, whisk the oil with the sour cream, eggs and vanilla.
4. 4Add the sour cream mixture to the dry ingredients. Using an electric mixer, mix on low until the dry ingredients are moistened, then turn the mixer to medium-high and mix for 2 minutes, scraping the bottom and sides of the bowl halfway through. Carefully fold the coffee into the batter using a flexible spatula.
5. 5Divide the batter evenly into the prepared pans and tap them on the counter a few times to release any large air bubbles. Bake until puffed and a toothpick inserted into the center comes out clean, 35 to 40 minutes. Set the pans on a wire rack and let the cakes cool for about 20 minutes. Next, run a thin knife around the edges of the pan and carefully turn the cakes out onto the rack to cool completely. (You may have to tap the pans gently on the rack to release each cake.)
6. 6While the cakes bake, clean the mixing bowl and make the buttercream: Add the butter to the bowl and mix on medium-high until smooth, stopping the mixer occasionally to scrape the bottom and sides of the bowl. Add the confectioners' sugar, cocoa powder, sour cream, milk, vanilla extract and salt. Mix on low until the sugar and cocoa are moistened, then turn the speed up to medium-high and whip until smooth and fluffy, about 5 minutes, adding a bit more milk (1 teaspoon at a time) if necessary to make a smooth and light buttercream. Scrape the bowl occasionally to ensure that the buttercream is evenly mixed. Taste and add a bit more salt if desired. (The buttercream can be kept at room temperature while the cake finishes baking and cooling.)
7. 7Assemble the cake: Just before frosting the cake, stir the buttercream vigorously with a flexible spatula to knock out any large air bubbles. (This will help to make the final buttercream smooth.) Add a small spoonful of buttercream to a serving plate or cardboard cake round and place one layer of cake on top, puffed-side down. Spread about 1 heaping cup of buttercream evenly over the top of the cake. Place the second layer on top of the buttercream, puffed-side down, and press gently. Spread a thin layer of buttercream over the top and sides of the cake (be careful not to transfer crumbs back into the bowl of frosting), then refrigerate the cake until the buttercream is firm, about 30 minutes.