01 -
Preheat the oven to 350°F (180°C) and line a 12-cavity muffin pan with muffin papers.
02 -
In a large bowl, whisk together flour, cocoa powder, baking soda, baking powder, salt, and sugar.
03 -
In a separate bowl, whisk together oil, egg, vanilla extract, and buttermilk until well combined and no visible egg pieces remain.
04 -
Create a well in the dry ingredients. Pour the wet ingredients into the well and whisk until about 60-70% mixed. Gradually pour in hot coffee and whisk until batter is smooth.
05 -
Spoon the batter into the prepared muffin pan, filling each cavity halfway. Ensure you get 11 or 12 cupcakes.
06 -
Bake on the middle oven rack for 16-20 minutes, or until the tops feel slightly firm and a toothpick inserted in the center comes out clean. Cool in the pan for 10-20 minutes before transferring to a wire rack.
07 -
Using a mixer, beat butter until fluffy. On low speed, mix in 2 cups of powdered sugar, vanilla extract, and salt until combined. Gradually add cocoa powder, remaining powdered sugar (1/2 cup at a time), and cream until desired consistency is achieved.
08 -
Frost cooled cupcakes using a piping bag with a preferred tip or a flat-edge knife. Optionally add chocolate chips or sprinkles for decoration.