A Well-Timed Murder by Tracee de Hahn
This is the second in the series featuring Agnes Lüthi, but I didn't read the first and felt like this one worked quite well on its own. I do think reading #1 first would give you more insight into Agnes and what she's been though. It took me a while to connect with her, and I think if I had read the first, I would have already been invested in her when I started this one. Agnes feels like a real person, calm and intelligent, juggling work and life. She's a widow with two children and while I usually prefer my detectives to not have children, unless the children are adults with their own lives, I didn't find it too distracting here.
Agnes is asked to investigate the death of a well-known watchmaker, Guy Chavanon. His death has been ruled an accident, a result of contact with peanuts, which he's allergic. Of course, it's not a simple accident and we find that...