Make ganache by warming the 100g milk chocolate and 50ml double cream, then freeze 8 teaspoons worth
Mix the melted butter and sugars
Add the egg, egg yolk and vanilla
Stir through the flour, cocoa powder, baking powder and salt
Fold through the chocolate chunks, saving around 10% to put on top
Take a spoonful of dough and wrap around a frozen ganache centre
Freeze for at least 1 hour before baking
Bake at 180°C fan for 12-14 minutes
Top with the remaining chocolate chunks fresh out of the oven
