First make the ganache. Take cream in a sauce pan and bring it to a simmer. Now add in chopped chocolate and mix well. Once it is all melted. Take it off the heat and set aside to set. It will take 2 to 3 hours.
Preheat oven to 180 degree C. Line a 12 cup muffin pan with cupcake cases and set aside.
Take cocoa powder in a bowl, add in 4 tblsp of hot milk and mix well.
Add in butter, sugar and eggs and mix well.
Add vanilla and mix well.
Now add in dry ingredients into this and fold gently.
Scoop this into cupcake cases and bake for 20 to 25 mins.
Remove and cool completely.
Now frost with ganache and serve.