Preheat the oven to 350°F (175°C).
Line a 12-cup pan with cupcake liners and prepare 2 more liners (this recipe makes 14 cupcakes). Set aside.
Whisk together the hot coffee and cocoa powder until smooth. Set aside.
In another bowl, sift the flour, baking soda, baking powder and salt together. Add the sugar and whisk until combined. Set aside.
In another bowl, add the buttermilk, oil, and egg and whisk everything together until well combined.
Add the coffee mixture to the oil mixture and whisk until it's just combined.
Add the flour mixture and whisk until combined, but don't overmix.
Pour the batter into the cupcake liners halfway full (I like pouring the batter into a pitcher first to avoid making a mess).
Bake for about 20 minutes, or until a toothpick inserted in the middle comes out clean.
Cool completely before frosting.