On Pesach My mother makes a cereal out of Matza farful and nuts and cinamon. The pieces of matza are big enough to be noticed as Matza, does one need to wash when eating a bowl of this with milk?

Usually farfel, though noticible, is too small to be called bread. If the cereal is made of broken peices of Matza which are larger, it would be advisable to wash and make a Motzi on regular Matzah before eating the cereal.