The Familiar by Leigh Bardugo

FATE CAN BE CHANGED.
CURSES CAN BE BROKEN.

In a shabby house in the new capital of Madrid, Luzia Cotado uses scraps of magic to get through her days of endless toil. But when her scheming mistress discovers her scullion is hiding a talent for little miracles, she demands Luzia use those gifts to win over the royal court.
Determined to seize this chance to better her fortunes, Luzia plunges into a world of power-hungry nobility, desperate kings, holy men and seers, where the lines between magic, science and fraud blur. With the pyres of the Inquisition burning, she must use every bit of her wit and resilience to win fame and hide the truth of her ancestry – even if that means enlisting the help of an embittered immortal familiar, whose own secrets could cost her everything.
From the Sunday Times bestselling author comes a bewitching novel, brimming with peril in a world where a woman’s ambition can prove deadly.