• Preheat the oven to 325 degrees. Grease and flour three 8x2 inch round cake pans. Place a piece of parchment in the bottom of each pan.
• Put the first 5 ingredients into the bowl of your mixer. Mix on low speed for at least 30 seconds to combine.
• Add the softened butter (cut into pieces) mix on low speed just until it looks like coarse sand. The dry ingredients will be moistened/coated by the butter and will stick to together if you press some between two fingers. Don't over-mix or it will turn into a large dough-like ball.
• Add the eggs one at a time, mixing until blended. 
• Add the vanilla to the 1 ¼ cup buttermilk. With the mixer on lowest speed gradually pour into the mixer. Increase the speed to #2 or # 3 (on a KitchenAid mixer). Mix for 2 minutes. Batter will be fluffy and smooth. If you are using a hand mixer rather than a stand mixer, you will need to mix a bit longer.
• Divide batter evenly between your three prepared (8 inch) pans.
• Bake at 325 degrees for 25 to 30 minutes. Cool for 5 minutes and turn out of pans. 

For the Chocolate Buttercream Frosting

• Add butter and mix on low to medium speed until smooth. Add vanilla and blend into the butter. Add powdered sugar, salt, and cocoa powder.
• Add most of the milk. Begin mixing at low speed so you won't have a cloud of powdered sugar in your kitchen.
• Continue to mix adding remaining milk as needed. It may take 5 to 6 minutes to reach the smoothness and consistency you like. It will take longer if using a hand mixer. As you mix, the frosting will become very smooth. You can add additional milk (1 Tablespoon at a time) if the frosting is too thick or additional powdered sugar if too soft.
• This is my favorite chocolate frosting! Recipe can easily be doubled or halved. This recipe makes approximately 6 cups of frosting.