Cinders and Sparrows by Stefan Bachmann

A suspenseful tale of witches, family, and magic from internationally bestselling author Stefan Bachmann. When a twelve-year-old orphan unexpectedly becomes the mistress of a seemingly abandoned castle, she is thrust into a mysterious plot involving murderous spells, false identity, and a magical battle of wills between the living and the dead. Readers of Kate Milford's Greenglass House, Victoria Schwab's City of Ghosts, and Diana Wynne Jones will be riveted.
Twelve-year-old Zita, an orphan and a housemaid, has resigned herself to a life of drudgery when a strange letter arrives, naming her the only living heir to the Brydgeborn fortune. Now the mistress of the castle, Zita soon realizes foul play led to the death of her family. And as she is guided through lessons in the art of witchcraft by the somewhat mysterious Mrs. Cantanker, Zita begins to wonder who is friend and who is foe.
Unforgettable and utterly enchanting, this stand-alone tale about family, belonging, and friendship will bewitch readers of Tahereh Mafi's Whichwood, Katherine Arden's Small Spaces, and Diana Wynne Jones's Howl's Moving Castle. Cinders & Sparrows is a magical page-turner by the author of The Peculiar, the acclaimed international bestseller.