01 -
Preheat oven to 175°C and line a 12-cup muffin tin with paper liners.
02 -
In a bowl, whisk together flour, cocoa powder, baking soda, baking powder, and salt until evenly mixed.
03 -
In another bowl, whisk melted butter, granulated sugar, brown sugar, eggs, and vanilla extract until smooth.
04 -
Add dry ingredients alternately with buttermilk to the wet mixture, beginning and ending with dry ingredients. Mix gently until just combined.
05 -
Slowly stir in hot coffee or hot water, then fold in chocolate chips if using.
06 -
Divide batter evenly among muffin liners, filling each about two-thirds full. Bake for 18 to 20 minutes or until a toothpick inserted into the centre comes out with moist crumbs.
07 -
Allow cupcakes to cool completely on a wire rack before frosting.
08 -
Melt butter in a saucepan over medium heat. Stir in cocoa powder and whisk until smooth, then remove from heat.
09 -
Gradually incorporate sifted powdered sugar alternately with heavy cream or milk, whisking until a thick, creamy texture forms. Stir in vanilla extract and a pinch of salt. Adjust consistency with more cream if needed.
10 -
Let frosting cool slightly, then spread or pipe onto cooled cupcakes as desired.