Preheat oven to 325 degrees. Line a cupcake pan with liners and set aside.
In a large bowl, whisk or sift together dry ingredients : flour, cocoa powder, baking soda, baking powder, and salt. Set aside
In a separate bowl, add your wet ingredients: granulated sugar, eggs, buttermilk, warm water, vegetable oil, and vanilla extract. Mix until combined.
Add half of dry ingredients to wet ingredients and stir until just combined. Add remaining dry ingredients and mix until just combined
Divide cupcake batter between 18 cupcake liners, filling about halfway full. Bake in preheated oven for 18-20 minutes, or until a toothpick comes out clean.
Remove pan from oven and allow to cool for 5 minutes before transferring cupcakes to a wire rack to finish cooling.