To make the cake I take a small amount of water, about ¼ cup, heat it up and add the espresso powder. I then add the remaining water needed as per the cake mix instructions. Mix the rest of the ingredients needed to make the cake. Stir in a couple handfuls of chocolate chips if you like. Bake according to package directions.
Make frosting by mixing powdered sugar, cocoa powder, dash of salt, vanilla and milk. I start with about 2 tablespoons of milk and gradually add more to get a nice consistency so that the frosting isn't too thick or too thin.
Frost the cake when cool. Sprinkle with chocolate chips or shave a little dark chocolate over the top.