Baking Two 6-inch Layers of Chocolate Cake

1. Preheat your oven to 350°F. Butter and flour two 6” round cake pans or coat them with baking release spray. I use damp cake strips on my pans for more evenly baked layers.
2. To a large bowl, add and whisk together all-purpose flour, brown and granulated sugar, dutch processed cocoa powder, baking powder, baking soda, espresso powder, and kosher salt. Set aside.  
3. In a smaller mixing bowl, whisk together your vanilla extract, eggs, greek yogurt or sour cream, buttermilk, and oil. 
4. Pour your hot water into the bowl of dry ingredients so your cocoa powder can bloom. Mix until fully combined, and then pour all ingredients into your larger bowl. Mix again until everything is fully incorporated. 
5. Pour and evenly spread the batter into your prepared cake pans. Bake for 33-38 minutes or until layers bounce back at the touch of your finger.
6. Let cakes cool in pans for about 10 minutes before transferring to a wire rack to cool completely before frosting.

Instructions for Chocolate Frosting

1. In the bowl of your stand mixer, combine your unsalted butter, powdered sugar, cocoa powder(s), vanilla extract, heavy cream, and salt. Start mixing on a low setting in short spurts to incorporate and avoid powder flying everywhere. Then increase speed and beat for another 5 minutes.
2. Once happy with flavor, use a spatula to smooth the frosting. Drag the spatula from the middle of your bowl to its edges, watching as the tears and bubbles in your buttercream disappear. Spend 3-4 minutes doing these motions to achieve nice, smooth frosting. If the frosting is too thick to easily spread it, add one tablespoon of heavy cream at a time into your bowl. If too thick, add ¼ cup of powdered sugar and mix.
3. Once the consistency is smooth, transfer the frosting to a piping bag fitted with a tip of your choice.

Cake Assembly Instructions

1. Pipe or spread a dollop of chocolate buttercream onto a cake circle or cake board to hold the layer in place, then set the first cake layer on top. It should be very cold from resting in your freezer.
2. Pipe about a quarter of the frosting on top of the bottom layer. Spread it evenly using an offset spatula or large spoon.
3. Sprinkle your desired amount of sprinkles across the frosting layer for added color inside. Gently press them into the frosting with the back of a spoon.
4. Place the second and final cake layer on top. Pipe another quarter of the frosting onto its top and spread evenly.
5. Starting at the base, pipe a thick layer of frosting around the sides of the cake.
6. Use a cake scraper (or the back of a bench scraper) to smooth the frosting. Hold the scraper gently against the side and rotate the cake to remove air bubbles and create an even surface. Leave the "crown" of frosting on top for a rustic, simple look, or smooth it out if preferred.
7. Scatter a thin layer of sprinkles over the top of the cake. For the base, place a band of sprinkles around the cake circle or decorating stand. Gently press them against the sides of the cake using a knife or the back of a spoon.