• Preheat the oven to 350° F.
• Prepare 2 8 inch or 9 inch cake pans by spraying with pan spray, lining the bottoms of the pans wth parchment, and spraying again. Set aside.
• Whisk together the cocoa powder and water until smooth.
• Whisk the cake flour and baking powder together very well. Set aside.
• In the bowl of a stand mixer, cream butter until smooth. Add the sugar and salt and cream until light and fluffy, about 3 minutes on medium speed. Scrape bowl often to make sure all the butter is incorporated.
• Add the eggs, one at a time, beating for about 20 seconds between additions and scraping bowl frequently. Beat in the vanilla.

Add the dry ingredients alternately with the water/cocoa powder mixture in this order:

• ½ of the dry ingredients
• ½ of the cocoa mixture
• ½ of the remaining dry ingredients
• the rest of the cocoa mixture
• the rest of the dry ingredients
• After each addition, beat on low speed just until combined, scraping the bowl to make sure all the ingredients are incorporated.
• Divide mixture evenly into the prepared pans and bake until the cake springs back when lightly pressed in the center, about 25-35 minutes, depending on your oven.

To Assemble

• You can assemble this cake in one of two ways. You can stack the two layers on top of each other with some frosting in between, or you can slice each cake layer in half horizontally. This will give you a total of four layers and three layers of filling. Either way is acceptable.
• Using a serrated knife, cut the dome off the cake layers, leaving you with flat layers. This is an optional step but will leave you with a nice, flat, professional-looking cake.
• Place a tablespoon of frosting in the center of your serving platter. This will act as glue to keep your cake from sliding.
• Position one cake layer, top side up, in the center of your platter. Press down gently so the icing sticks.
• Fill the cake with about ½ - ¾ cup of frosting, spreading to within ¼ inch of the edge. Use ⅓ - ½ cup per layer if you choose to make a four-layer cake.
• Position the second layer, bottom side up, on top of the frosted layer, making sure the edges are even all the way around. Placing the layer bottom side up gives you a flat top surface that is relatively free of crumbs.
• Using a pastry brush, brush off any loose crumbs.
• Ice the sides and top of the cake with a very thin layer of frosting. This is the crumb coat which will allow you to add a second layer of frosting without worrying about crumbs marring the finish.
• Refrigerate the cake for about 15 minutes to let the crumb coat set up.
• Ice the sides and top of the cake with the finish coat. This coat can be thicker. Aim for about ¼ inch of frosting.
• Decorate as desired.