Preheat oven to 350 degrees F.  Grease and flour 3 (8x2) round pans

In a medium bowl combine the flour, baking powder, baking soda, salt, and cocoa powder.  Whisk for 30 seconds to blend and set aside.

In a separate bowl, add the milk and vanilla. Set aside.

In the bowl of an electric mixer, (using a paddle attachment if using a stand mixer), add the softened butter and softened cream cheese.  Mix until smooth.  Gradually add the sugar.  Mix on medium speed for 3 minutes until fluffy.  Scrape the sides and bottom of the bowl.

Add the eggs one at a time, mixing after each until the yellow of the yolk has blended.

Prepare the ½ cup of very hot water for the next step.

With the mixer on low speed, add about ⅓ of the flour mixture, followed by the milk, then half of the remaining flour mixture followed by the very hot water, and end with the remaining flour mixture. Mix just until incorporated.

Add the batter to the three prepared pans and bake at 350 degrees  for 25-30 minutes.  The cake layers are done when a toothpick inserted into the center comes out clean or with just a few crumbs attached. 

Cool the  pans on cooling rack 5 to 10 minutes then turn out. 

Cut the butter into slices and add to the bowl of your mixer. Beat on low to medium speed until the butter is softened and smooth.

Add cocoa and mix until blended.

Cut the cream cheese into pieces and add to the butter, beating at low to medium speed until incorporated.

Add the vanilla. Gradually add the powdered sugar beating on low speed until blended.

Increase mixing speed to medium and beat until fluffy, don't over beat. If beaten too long it will become very soft. If this happens, just refrigerate for 10 to 15 minutes.

This frosting will pipe best if used while still very cool. You can make it in advance, refrigerate and when ready to use let it soften slightly (do not microwave) and remix.

Will frost a 3 layer 8 or 9 inch cake.

After applying my final coat of frosting, I went over it with a bench scraper (or spatula) and then combed it with a cake comb. Remove the excess frosting around the top edge of the cake with a spatula. I then applied top and bottom borders with a petal/ruffle tip 104 as well as a few dots on top with a tip 3.