Line the bottom of a 9-inch spring form pan with parchment paper. Spray the inside (including the parchment paper) with baking spray. Alternatively, you can brush it with butter and lightly flour it. Set it aside for now.
In your mixing bowl, combine the flour, sugar, baking cocoa, baking soda, baking powder, salt, and instant espresso powder. Stir these together.
Add in the milk, extra virgin olive oil, egg, and vanilla extract. Mix to combine. Then add the very hot water. Mix thoroughly, scraping the bowl with a rubber spatula. Your batter will be very thin, but that is normal.
Pour the batter into your prepared pan and bake for 30-35 minutes, or until the cake tests done in the center with a wooden pick.
Allow the cake to cool for 5 minutes, then run a knife around the sides to make sure nothing is sticking. Remove the sides of your spring form pan and cool the cake on a rack until room temperature.
For the Frosting:
Beat the butter in your mixing bowl until fluffy (use the whisk attachment.)
Add in the baking cocoa, powdered sugar, vanilla extract, and milk.
Mix until smooth and creamy. Add small amounts of additional milk if needed to make this a nice, spreadable frosting.