• In a large mixing bowl add the eggs, sour cream, vanilla extract, and oil. Mix well until the wet ingredients are combined.
• Next, add the dry ingredients (flour, brown sugar, white sugar, baking powder, baking soda, salt, and cocoa powder) to the wet ingredients.
• Whisk the ingredients and scrape the sides of the bowl.
• Pour in the hot coffee and mix until just combined. The chocolate cake batter should be liquid.
• Line two round 6-inch cake pans with parchment paper and divide batter in half.
• Bake the layers in a 350F preheated oven for 25 minutes or until a toothpick is inserted and is clean or has moist crumbs sticking on to it.
• Allow the layers to cool for 15 minutes before flipping them over on a cooling rack to let them cool.

Vanilla Buttercream

• In a stand mixer add unsalted butter in the bowl and whip on high speed for minutes.
• Add in the powdered sugar and whip on low speed until the powdered sugar is mixed in and then whip medium speed for 5 minutes.
• Add in vanilla extract and heavy cream and continue to whip for another minute or two. Scrape the sides and bottom of the bowl and then set aside until needed.

Small Chocolate Cake Assembly

• Place a chocolate cake layer on a cake stand and then add the vanilla buttercream.
• Use an offset spatula and evenly spread the buttercream and then place the top layer of the chocolate cake on top.
• Spread a thin layer on crumb coat all around the cake and then refrigerate for 15 minutes or until the cake is set enough to frost the outside of the cake.
• Cover the cake with the remaining frosting and then top with sprinkles.