This is one of the eggs, that I felted last year with the kids. It is handfelted with soap and warm water. I did not have a felting needle then.
The base is a plastic Easter egg and I put some roving around it. It was quite difficult to get it nice and even, but putting it in a plastic bag normally used for sandwiches helped. When it was halfway felted, I wound the coloured yarn around it. It took much longer than I expected and if I had to do it again, I would try needle-felting.