Cream the butter and sugars together in a large bowl until smooth and fluffy with electric whisk.
Add the eggs and vanilla extract, then mix until fully combined.
Add 1 bag of chopped mini eggs, flour, baking soda and salt, then mix until a soft cookie dough forms.
Place dough into a ceramic dish and bake at 180°C (350°F) for 15-20 minutes, 2 minutes before baking push the remaining mini eggs and decorate with the chocolate buttons. Bake until golden on the edges and soft in the centre.