blessings on Margaret Frazer...

...and yes, I realize that Margaret Frazer isn't a real person. She's a pen name for two authors (Gail Frazer and another author at first; now, it's just Gail Frazer) who write a mystery series about Dame Frevisse, a 15th-century nun. If you haven't read them, start with The Novice's Tale.
Yes, I know - what is it with me and nuns? Well, I finally figured that out: the attraction is not only the struggle with one's vocation, but also the interest I have in all-woman communities. That's why I like the minutiae of girls' boarding school stories: how is the school laid out? How are prefects chosen, what are their responsibilities, and how much power do they have?
But I digress. Dame Frevisse develops as a character throughout the series, and her interactions with the world outside her convent are well explained (otherwise, how could there be so many violent deaths in a small convent?). Frazer avoids too many Famous Person Cameos (I always hate those), the books are reasonably accurate, and the recurring characters are well developed and well used. My favorite so far is The Servant's Tale, which had an agreeably creepy ending, though The Boy's Tale made me teary at the end.
Side note to the person who recommended the series to me: I wrote a garbled note to you on odd stationery. Sorry! I was in a hurry to thank you, so I mailed it anyway. The note was a poor shadow of my gratitude to you for recommending these books! I don't always write gibberish, by the by.