In a bowl mix together cocoa, sugar, vanilla and butter.
Add milk and red food colour and beat until incorporated.
Add flour and baking powder and mix to form a loose dough.
Cover with cling wrap and refrigerate for 4 hours.
Mix together icing sugar and corn flour in a bowl and set aside.
Once the dough is firm, remove it from fridge and divide into 21 equal portion.
Arrange them on a plate and refrigerate them again for 30 minutes.
Preheat oven to 175°C.
Remove the chilled dough and roll them to form a ball.
Roll them generously in the icing sugar mixture and arrange on a greased tray.
Bake them for 12 - 15 minutes until slightly firm to touch.
Remove from oven and allow it to cool on the tray for 5 minutes.
Remove from the tray and cool on a wire rack.
Store in airtight jar.
