Minnie Mude works at the post office as a maid.
She is a bit silly and she daydreams quite a bit. However she has quite a seroius past. Her stepfather was cruel to her and her two sisters ran away and got into trouble to escape him. Minnie signed her own indenture papers to also get away.
In season 2, Dorcas is sick so Laura has to run the post office. She begins to get notes saying terrible things and a broken china doll. They are all addressed to "girl at the post office, candleford", and Laura initially thinks they are meant for her. Later, they discover that they are really meant for Minnie and are from her stepfather.