Basil Instinct

"A top secret society of female chefs, Belfiere has marinated in mystery for two centuries. With its members-only tattoo and code of omerta (silence), this is not your grandmother's cooking circle. Or so Eve Angelotta thought, until her own Nonna--Miracolo's feisty owner, Maria Pia--is chosen to join their shadowy ranks. When you let fifty masked Belfiereans with a lot to hide into your dining room, can murder be far behind?" -- from author's web page.