Preheat your oven to 180 degrees (fan forced) and line the a muffin tray with paper cases.
Set aside 12 Caramilk Easter Eggs and roughly chop the remaining Easter Eggs into small pieces. Place them into a bowl and lightly coat with the extra flour. Set aside until needed.
Place the butter (which has been cubed) into your Thermomix bowl and melt for 2 minutes at 65 degrees on speed 2.
Add the self raising flour, cocoa, caster sugar, eggs, milk and vanilla essence to your Thermomix bowl and mix for 5 seconds on speed 4 before scraping down the sides and mixing for a further 7 seconds on speed 4 or until combined.
Add the chopped and floured Caramilk Easter Egg pieces and use a spatula to gently fold through the mixture.
Divide the mixture amongst the paper cases and bake for 15-18 minutes or until a skewer inserted in the middle comes out clean.
Allow the cupcakes to cool in the tin for five minutes before transferring to a wire rack to cool completely.
Once the muffins have cooled, combine the icing sugar mixture, cocoa, butter and boiling water until smooth. Ice each muffin and decorate with one of the Easter Eggs set aside earlier.