Place the Cadbury mini eggs in a large bag, with the back of a tablespoon hit each egg and they'll pop in half.
Cream the butter and the sugars in an electric mixer until light and fluffy.
Add eggs one at a time; mixing with each addition.
Add vanilla.
Add the flour; mixing until 80% incorporated.
Add the chocolate chips and and cadbury mini eggs and use a wooden spoon to blend together.
Roll into 1 inch balls or use an ice cream scoop to dollop the dough onto the baking tray.
Bake at 180 degrees for 9-10 minutes until the edges are slightly browned.
Let them rest on the baking tray or greaseproof paper for 1 minute, then transfer to a rack to cool.