Pre-heat your oven to 180C/160C Fan/350F/Gas Mark 4 and line a cupcake tin with paper cases
To make the cupcakes, cream together the butter and caster sugar until smooth
Add the eggs and vanilla, and mix well
Add the self raising flour and whisk in
Divide the mixture between the cupcakes cases, and bake them for 20-25 minutes until then are golden brown. Put them on a rack to cool completely
To make the chocolate buttercream, mix together the butter, icing sugar and cocoa powder. When it starts to come together, add the milk and mix until smooth
Pipe the buttercream onto each cupcake using a piping bag fitted with a Wilton 233 nozzle to make a nest. Add three different coloured mini eggs in the centre
Store in an airtight container in a cool place, eat leftovers within 3 days