Homemade Chocolate Cake with Chocolate Buttercream Frosting

Ingredients

• ¼ cup butter for greasing pans
• 3 cups flour
• 1 ½ cups cocoa, plus extra for preparing pans
• 1 tbsp baking soda
• 1 ½ tsp baking powder
• 1 ½ tsp salt
• 3 cups sugar
• 4 eggs
• 1 ½ cups buttermilk
• 1 ½ cups water
• ½ cup fractionated coconut oil or vegetable oil
• 2 tsp vanilla
• 2 cups (4 sticks) butter, softened
• 16 oz confectioners' sugar
• 1 cup cocoa powder
• ½ tsp salt
• 3 tbsp milk