Preheat oven to 350°F. Line cupcake pan with liners and set aside.
In bowl of an electric mixer whisk the flour, sugar, cocoa powder, baking soda, baking powder, and salt.
In a large liquid measuring cup whisk the egg, buttermilk, hot water (or coffee), oil and vanilla.
Add wet ingredients to the dry ingredients and mix on medium speed for 2 minutes. Scrape the sides of the bowl with a spatula and mix for another 30 seconds.
Scoop (pour) the batter into the cupcake liners, the batter is very very thin, filling only halfway full, or up to 2/3 full but no more!
Bake for 13-16 minutes or until a toothpick inserted in the center comes out with moist crumbs. **
Remove from the oven and allow cupcakes to cool in pan for 10 minutes. Transfer to wire rack to cool completely.